Merge branch 'release/1.2.1' into develop
test on python 3.2
add support for python 3 in tests, common, and git
all unit tests pass with python 3.2
use exec() instead of execfile() for python 3 support
tell travis to only install unittest2 for python 2
use script to install requirements for travis
test on python 3.0, 3.1, and 3.3
remove travis testing of python 3.0 and 3.1

travis-ci does not support these versions
update supported python versions
Merge branch 'feature/python3-support' into develop
add copyright to LICENSE and make license version more clear
work on README

Use ReStructuredText instead of Markdown, since pypi doesn't speak Markdown.
Explain more about what the library is and does.
document load() and dump() in README
only use first parent in pdiff() and changed()

Use -c instead of -m for git diff-tree

This closes issue #31
fix changed_copy_info_rx regular expession

This fixes bug #30
re-add README symlink
bump version to 1.2.2
update release notes
Merge branch 'release/1.2.2'