Misc cleanup

Fix lint
Pass kwargs straight through to fn that uses them
Add django 1.7 to ci build

Silence warnings from 1.7 test runner
Add support for passing kwargs to csv writer

fixes #54 on github
fixes #56 on github

Bump version number for release
Add unit tests
Update documentation
Merge pull request #58 from azavea/topic/54_56_add_support_for_csv_kwargs

Topic/54 56 add support for csv kwargs