Fixing sympy profile.

Lots of work on the display system, focused on pylab stuff. * Moved the pprint attribute to PlainTextFormatter. * Added DisplayFormatter.plain_text_only for disabling all but the plain text formatting. This is now used by doctest_mode. * Remove result_display hook. * Fixed doctest_mode magic. * Refactored inline matplotlib backend to use new display system. * Added display formatter for matplotlib.figure.Figure objects. so the display system will show the svg for them. * Added display and display_png to the user's namespace in pylab. * Cleaned up pylabtools.py

More improvements to the display system. * Full PNG handling in the rich frontend. * Sympy printer now can render to latex->png.

Display system is fully working now. * Top-level display function. * The follow MIME types are supports: text/plain, text/html, text/latex, image/png, image/svg+xml, application/json. * All display data is published to all frontends. * Currently the qtconsole handles text/plain, text/html and image/svg+xml data.

Mostly final version of display data. * New publish_display_data function. * backend_inline is using publish_display_data. * Documentation added.

Initial version of DisplayPublisher is working. * Backend and frontend implementations. * plain text, html and svg handlers in the Qt console.

Initial draft of repr_data message type.

Merge branch 'takowl-fix-terminal-exit' into trunk

Updating comments and docstrings for history autosave.

Merge branch 'minrk-session.send' into trunk

add docstrings, per review.

Rework history autosave, so that the timer thread sets an event, and the save is performed in the main thread after executing a user command.

all sends/recvs now via Session.send/recv. This allows changes to protocols/patterns to happen in a single location.

Defining system default encoding in log file header comment.

Encode data with system default encoding before writing to log file. This enables writing non-ascii characters to be written in log file during logging session.

Yet more revisions to the wildcard module.

Make ipython.py cProfile-able When using __file__ on startup and cProfile in the same time, __file__ is defined as the __file__ of cProfile and not the local ipython.py. With using sys.argv[0] instead, it's possible to get a cProfile.

Further tidying up of IPython.utils.wildcard.

Simplify and tidy up IPython.utils.wildcard.

Fix for issue 129. Tests in previous commit now pass.