Updated the 'Installing Astropy in develop mode' section (use setup.py develop in the first instance, added a link to the instructions on how to run the tests, which required adding a label to install.rst), added some additional links to GitHub pages, fixed some typos, applied other minor edits for clarity / consistency
Provides a workaround for the OSX bug that causes #839
Simplified the branching logic a bit and added a changelog entry.  Also removed a Sphinx-specific directive from the changelog (just for now--I need to revist whether or not we want to be able to render the changelog without Sphinx).
Use the local implementation of PyErr_NewExceptionWithDoc on Python 3.1 as well.
Merge pull request #839 from iguananaut/issue-839

Issue with astropy.io.fits and large arrays
Merge pull request #1212 from ehogan/dev-workflow-doc-improvements

Updated the 'Installing Astropy in develop mode' section ...
Added a note that setup.py develop won't work in Python 3 per #1126
Removed reference to 'forking action' as it was taken out of GitHub a while ago as well.
Fix #1232: powers are now displayed as integers or fractions, not floating point, in all formatters
Fix some compiler warnings
Fix coding in units/test/test_format.py
Merge pull request #1275 from mdboom/wcs/python31-new-exception-with-doc

Units and WCS failures with Python 3.1
Merge pull request #1126 from iguananaut/issue-1126

python3 incompatibility in configuration.py when using virtualenv + python setup.py develop
Added changelog entries for all the fixes in 0.2.4.