Reenabled the test test_asyncfrontendbase.py. For some reason this was being skipped by nose. Re-enabled and all tests pass.

Removed the top-level iptest.py and INSTALLED logic. Fernando's branch introduced the ability to run the test suite from a top-level iptest.py script. This allowed IPython to be tested without installation. The implementation was fragile and we also decided that we *want* people to install IPython as part of testing it, so we removed this feature.

More work on the crash handler. * Made a subclass of :class:`IPython.core.crashhandler.CrashHandler` for each application we have. Each of these has a custom message and uses the name and email of the appropriate personf for that app. * Removed the :meth:`IPython.core.application.abort` method. * Made small changes to how the crash handler is instantiated in :class:`IPython.core.application.Application`. * Tested the crash handlers.

Fixed broken test in :mod:`IPython.utils.tests.test_path`.

Fixed bug in ultratb.py and io.py. Previously :class:`IPython.utils.io.Term` had a :meth:`Term.writeln` method that :mod:`ultratb.py` was using. But, when a real stream or files is used in :class:`IPython.utils.io.Term` it doesn't have this method, so we were getting an error when the IPython Sphinx directive was run. I removed this method and made :mod:`ultratb.py` use just ``write``.

Fixed small bug in ipcluster. Some of the subparsers in ipcluster were not having the argument_default=SUPPRESS option passed to them so there were getting None as a default, which was overriding the config system defaults.

Removed IPython.config.default from the default search path for ipcluster When ipcluster searches for config files, it should not look in IPython.config.default because we ALWAYS move the default config files to cluster_dir (which is still on the search path).

Refactored the command line config system and other aspects of config. * Removed ``NoConfigDefault`` from our config logic entirely. It turns out that argparse has a nice ``argparse.SUPPRESS`` object that handles this nicely (r1283, r1284). * Completely cleared the previous config when :meth:`load_config` is called to allow it to be called more than once. * Added some additional tests and docs for the config system. * Removed the ``override_config`` and ``constructor_config`` config stages from :class:`~IPython.core.application.Applications` (r1293). * Completely refactored the command line config parser classes. We are now using a more object oriented design that allows for fine grained inheritance and good encapsulation.

Work on the config system. * Removed ``NoConfigDefault`` from our config logic entirely. It turns out that argparse has a nice ``argparse.SUPPRESS`` object that handles this nicely. * Completely cleared the previous config when :meth:`load_config` is called to allow it to be called more than once. * Added some additional tests and docs for the config system.

More work addressing review comments for Fernando's branch. * :mod:`IPython.testing.globalipapp` now directly creates a :class:`~IPython.core.iplib.InteractiveShell` instance by passing it a configuration object, rather than creating an IPython application. * Updated everything in :mod:`IPython.frontend` and :mod:`IPython.gui` to use raw :class:`~IPython.core.iplib.InteractiveShell directly rather than creating an IPython application. * Updated the IPython sphinx extension to use raw :class:`~IPython.core.iplib.InteractiveShell directly rather than creating an IPython application. * Removed code from :mod:`IPython.extensions.pretty` that called :func:`get_ipython` (r1271). * Addressed comment on (r1284) about holding refs to deferreds in :mod:`IPython.kernel.ipclusterapp`. * Removed :mod:`IPython.kernel` from list of modules tested by nose in :mod:`IPython.testing.iptest`. (r1318)