Backport PR #5489: Fix required Python versions

It seems there's been a small inconsistency in documentation, which mentions Python 3.2.1 as minimum requirement for IPython 2.0. I've changed it to 3.3.0 - I don't know if there's 0 for minor version is sufficient, feel free to adjust it.

docs/source/whatsnew/version2.0.rst

@@ -1,324 +1,324 b''
 ============
  2.0 Series
 ============
 
 Release 2.0.0
 =============
 
 April, 2014
 
-IPython 2.0 requires Python ≥ 2.7.2 or ≥ 3.2.1.
-It does not support Python 3.0, 3.1, 2.5, or 2.6.
+IPython 2.0 requires Python ≥ 2.7.2 or ≥ 3.3.0.
+It does not support Python 3.0, 3.1, 3.2, 2.5, or 2.6.
 
 The principal milestones of 2.0 are:
 
 - interactive widgets for the notebook
 - directory navigation in the notebook dashboard
 - persistent URLs for notebooks
 - a new modal user interface in the notebook
 - a security model for notebooks
 
 Contribution summary since IPython 1.0 in August, 2013:
 
 - ~8 months of work
 - ~650 pull requests merged
 - ~400 issues closed (non-pull requests)
 - contributions from ~100 authors
 - ~4000 commits
 
 The amount of work included in this release is so large that we can only cover
 here the main highlights; please see our :ref:`detailed release statistics
 <issues_list_200>` for links to every issue and pull request closed on GitHub
 as well as a full list of individual contributors.
 
 New stuff in the IPython notebook
 ---------------------------------
 
 Directory navigation
 ********************
 
 .. image:: /_images/2.0/treeview.png
     :width: 392px
     :alt: Directory navigation
     :align: center
 
 The IPython notebook dashboard allows navigation into subdirectories.
 URLs are persistent based on the notebook's path and name,
 so no more random UUID URLs.
 
 Serving local files no longer needs the ``files/`` prefix.
 Relative links across notebooks and other files should work just as if notebooks were regular HTML files.
 
 Interactive widgets
 *******************
 
 .. image:: /_images/2.0/widgets.png
     :width: 392px
     :alt: Interactive widgets
     :align: center
 
 IPython 2.0 adds :mod:`IPython.html.widgets`, for manipulating
 Python objects in the kernel with GUI controls in the notebook.
 IPython comes with a few built-in widgets for simple data types,
 and an API designed for developers to build more complex widgets.
 See the `widget docs`_ for more information.
 
 .. _widget docs: http://nbviewer.ipython.org/github/ipython/ipython/blob/2.x/examples/Interactive%20Widgets/Index.ipynb
 
 
 Modal user interface
 ********************
 
 The notebook has added separate Edit and Command modes,
 allowing easier keyboard commands and making keyboard shortcut customization possible.
 See the new `User Interface notebook`_ for more information.
 
 .. _User Interface Notebook: http://nbviewer.ipython.org/github/ipython/ipython/blob/2.x/examples/Notebook/User%20Interface.ipynb
 
 
 You can familiarize yourself with the updated notebook user interface, including an
 explanation of Edit and Command modes, by going through the short guided tour
 which can be started from the Help menu.
 
 .. image:: /_images/2.0/user-interface.png
     :width: 392px
     :alt: Interface tour
     :align: center
 
 
 Security
 ********
 
 2.0 introduces a :ref:`security model <notebook_security>` for notebooks,
 to prevent untrusted code from executing on users' behalf when notebooks open.
 A quick summary of the model:
 
 - Trust is determined by :ref:`signing notebooks<signing_notebooks>`.
 - Untrusted HTML output is sanitized.
 - Untrusted Javascript is never executed.
 - HTML and Javascript in Markdown are never trusted.
 
 Dashboard "Running" tab
 ***********************
 
 .. image:: /_images/2.0/running-crop.png
     :width: 392px
     :alt: Running tab
     :align: center
 
 The dashboard now has a "Running" tab which shows all of the running notebooks.
 
 Single codebase Python 3 support
 --------------------------------
 
 IPython previously supported Python 3 by running 2to3 during setup. We
 have now switched to a single codebase which runs natively on Python 2.7
 and 3.3.
 
 For notes on how to maintain this, see :doc:`/development/pycompat`.
 
 Selecting matplotlib figure formats
 -----------------------------------
 
 Deprecate single-format ``InlineBackend.figure_format``
 configurable in favor of ``InlineBackend.figure_formats``,
 which is a set, supporting multiple simultaneous figure formats (e.g. png, pdf).
 
 This is available at runtime with the new API function :func:`IPython.display.set_matplotlib_formats`.
 
 clear_output changes
 --------------------
 
 * There is no longer a 500ms delay when calling ``clear_output``.
 * The ability to clear stderr and stdout individually was removed.
 * A new ``wait`` flag that prevents ``clear_output`` from being executed until new
   output is available.  This eliminates animation flickering by allowing the
   user to double buffer the output.
 * The output div height is remembered when the ``wait=True`` flag is used.
 
 Extending configurable containers
 ---------------------------------
 
 Some configurable traits are containers (list, dict, set)
 Config objects now support calling ``extend``, ``update``, ``insert``, etc.
 on traits in config files, which will ultimately result in calling
 those methods on the original object.
 
 The effect being that you can now add to containers without having to copy/paste
 the initial value::
 
     c = get_config()
     c.InlineBackend.rc.update({ 'figure.figsize' : (6, 4) })
 
 Changes to hidden namespace on startup
 --------------------------------------
 
 Previously, all names declared in code run at startup
 (startup files, ``ipython -i script.py``, etc.)
 were added to the hidden namespace, which hides the names from tools like ``%whos``.
 There are two changes to this behavior:
 
 1. Scripts run on the command-line ``ipython -i script.py``now behave the same as if they were
    passed to ``%run``, so their variables are never hidden.
 2. A boolean config flag ``InteractiveShellApp.hide_initial_ns`` has been added to optionally
    disable the hidden behavior altogether. The default behavior is unchanged.
 
 Using dill to expand serialization support
 ------------------------------------------
 
 adds :func:`~IPython.utils.pickleutil.use_dill` for allowing
 dill to extend serialization support in :mod:`IPython.parallel` (closures, etc.).
 Also adds :meth:`DirectView.use_dill` convenience method for enabling dill
 locally and on all engines with one call.
 
 New IPython console lexer
 -------------------------
 
 The IPython console lexer has been rewritten and now supports tracebacks
 and customized input/output prompts. See the :ref:`new lexer docs <console_lexer>`
 for details.
 
 DisplayFormatter changes
 ------------------------
 
 There was no official way to query or remove callbacks in the Formatter API.
 To remedy this, the following methods are added to :class:`BaseFormatter`:
 
 - ``lookup(instance)`` - return appropriate callback or a given object
 - ``lookup_by_type(type_or_str)`` - return appropriate callback for a given type or ``'mod.name'`` type string
 - ``pop(type_or_str)`` - remove a type (by type or string).
   Pass a second argument to avoid KeyError (like dict).
 
 All of the above methods raise a KeyError if no match is found.
 
 And the following methods are changed:
 
 - ``for_type(type_or_str)`` - behaves the same as before, only adding support for ``'mod.name'``
   type strings in addition to plain types. This removes the need for ``for_type_by_name()``,
   but it remains for backward compatibility.
 
 Formatters can now raise NotImplementedError in addition to returning None
 to indicate that they cannot format a given object.
 
 Exceptions and Warnings
 ***********************
 
 Exceptions are no longer silenced when formatters fail.
 Instead, these are turned into FormatterWarnings.
 A FormatterWarning will also be issued if a formatter returns data of an invalid type
 (e.g. an integer for 'image/png').
 
 
 Other changes
 -------------
 
 * `%%capture` cell magic now captures the rich display output, not just
   stdout/stderr
 
 * In notebook, Showing tooltip on tab has been disables to avoid conflict with
   completion, Shift-Tab could still be used to invoke tooltip when inside
   function signature and/or on selection.
 
 * ``object_info_request`` as been replaced by ``object_info`` for consistency in the javascript API.
   ``object_info`` as a simpler interface to register callback that is incompatible with ``object_info_request``.
 
 * Previous versions of IPython on Linux would use the XDG config directory,
   creating :file:`~/.config/ipython` by default. We have decided to go
   back to :file:`~/.ipython` for consistency among systems. IPython will
   issue a warning if it finds the XDG location, and will move it to the new
   location if there isn't already a directory there.
 
 * Equations, images and tables are now centered in Markdown cells.
 * Multiline equations are now centered in output areas; single line equations
   remain left justified.
 
 * IPython config objects can be loaded from and serialized to JSON.
   JSON config file have the same base name as their ``.py`` counterpart,
   and will be loaded with higher priority if found.
 
 * bash completion updated with support for all ipython subcommands and flags, including nbconvert
 
 * ``ipython history trim``: added ``--keep=<N>`` as an alias for the more verbose
   ``--HistoryTrim.keep=<N>``
 * new ``ipython history clear`` subcommand, which is the same as the newly supported
   ``ipython history trim --keep=0``
 
 * You can now run notebooks in an interactive session via ``%run notebook.ipynb``.
 
 * Print preview is back in the notebook menus, along with options to
   download the open notebook in various formats. This is powered by
   nbconvert.
 
 * :exc:`~IPython.nbconvert.utils.pandoc.PandocMissing` exceptions will be
   raised if Pandoc is unavailable, and warnings will be printed if the version
   found is too old. The recommended Pandoc version for use with nbconvert is
   1.12.1.
 
 * The InlineBackend.figure_format now supports JPEG output if PIL/Pillow is available.
 
 * Input transformers (see :doc:`/config/inputtransforms`) may now raise
   :exc:`SyntaxError` if they determine that input is invalid. The input
   transformation machinery in IPython will handle displaying the exception to
   the user and resetting state.
 
 * Calling ``container.show()`` on javascript display is deprecated and will
   trigger errors on future IPython notebook versions. ``container`` now show
   itself as soon as non-empty
 
 * Added ``InlineBackend.print_figure_kwargs`` to allow passing keyword arguments
   to matplotlib's ``Canvas.print_figure``. This can be used to change the value of
   ``bbox_inches``, which is 'tight' by default, or set the quality of JPEG figures.
 
 * A new callback system has been introduced. For details, see :doc:`/config/callbacks`.
 
 * jQuery and require.js are loaded from CDNs in the default HTML template,
   so javascript is available in static HTML export (e.g. nbviewer).
 
 Backwards incompatible changes
 ------------------------------
 
 * Python 2.6 and 3.2 are no longer supported: the minimum required
   Python versions are now 2.7 and 3.3.
 * The Transformer classes have been renamed to Preprocessor in nbconvert and
   their `call` methods for them have been renamed to `preprocess`.
 * The `call` methods of nbconvert post-processsors have been renamed to
   `postprocess`.
 
 * The module ``IPython.core.fakemodule`` has been removed.
 
 * The alias system has been reimplemented to use magic functions. There should be little
   visible difference while automagics are enabled, as they are by default, but parts of the
   :class:`~IPython.core.alias.AliasManager` API have been removed.
 
 * We fixed an issue with switching between matplotlib inline and GUI backends,
   but the fix requires matplotlib 1.1 or newer.  So from now on, we consider
   matplotlib 1.1 to be the minimally supported version for IPython. Older
   versions for the most part will work, but we make no guarantees about it.
 
 * The :command:`pycolor` command has been removed. We recommend the much more capable
   :command:`pygmentize` command from the `Pygments <http://pygments.org/>`_ project.
   If you need to keep the exact output of :command:`pycolor`, you can still use
   ``python -m IPython.utils.PyColorize foo.py``.
 
 * :mod:`IPython.lib.irunner` and its command-line entry point have been removed.
   It had fallen out of use long ago.
 
 * The ``input_prefilter`` hook has been removed, as it was never
   actually used by the code. The input transformer system offers much
   more powerful APIs to work with input code. See
   :doc:`/config/inputtransforms` for details.
 
 * :class:`IPython.core.inputsplitter.IPythonInputSplitter` no longer has a method
   ``source_raw_reset()``, but gains :meth:`~IPython.core.inputsplitter.IPythonInputSplitter.raw_reset`
   instead. Use of ``source_raw_reset`` can be replaced with::
 
       raw = isp.source_raw
       transformed = isp.source_reset()
 
 * The Azure notebook manager was removed as it was no longer compatible with the notebook storage scheme
 
 * Simplifying configurable URLs
 
   - base_project_url is renamed to base_url (base_project_url is kept as a deprecated alias, for now)
   - base_kernel_url configurable is removed (use base_url)
   - websocket_url configurable is removed (use base_url)