- use setuptools_scm to generate version number, normal releases will
use the tagged version (ie 1.9.1), versions installed from source will
append the git commit number to the version number (ie
1.9.1.dev61+g4584c93)
- use io.open() to read text files to correctly handle utf-8 characters
- use pip to parse requirements.txt
- update classifiers to specify python and django versions supported
- fix classifier for license
- wheel distributions can now be built using `python setup.py bdist_wheel`