Merge branch 'release/1.0.0'
Merge branch 'release/1.0.1'
Merge branch 'release/1.1.0'
Merge branch 'release/1.1.1'
Merge branch 'release/1.2.0'
Merge branch 'release/1.2.1'
Merge branch 'release/1.2.2'
Merge branch 'release/1.2.3'
Merge branch 'release/1.3.0'
Reorganize sphinx docs to more common format.
2 spaces to 4 spaces per PEP8. http://www.python.org/dev/peps/pep-0008/#indentation.
PEP8: over/under indentation. Fix ENOENT. 2-4
spaces on __init__, setup.py, tests.py.
test a working copy with identical files

This test suite creates a working copy with files with identical contents.  The
two files are created on different commits.  It exposes a couple of problems:

- Git: thinks the two files were made on the same commit
- Hg: doesn't report the commit
clean up and make CopyTest more robust

Test now considers three files:
  * an original file
  * a file with the same contents as the first
  * a file which also had the same contents, but has changed
    somewhere in between, and reverted

Other functional changes:
  - add new file to other test cases
  - removed some unnecessary flags
  - remove test_log2 altogether since it doesn't seem to add much

Other non-functional changes:
  - add some comments to describe the working copy created
  - coding style matching
revert indententation change in license
Merge branch 'tony-PEP8-indent' into develop
Merge branch 'tony-sphinx-reorganize' into develop
bump version to 1.3.1
Merge branch 'release/1.3.1' into develop
make GitRepo.empty() work correctly when there is no master branch

Also include test cases to expose the issue.

Issue #41