Added possibility to have max_length different than lenght
Merge pull request #1 from harrastia/add-max-length

Changed the logic to determine `max_length` field
PEP8 fixes
improved readability
moved charset generation to __init__
added support for django 1.7 migrations
updated README
added generate_charset method
updated setup.py
fixed Travis CI build status image
added/updated some docstrings
added django 1.7 beta to travis build
updated changelog
moved charset generation back to __init__
changed readme to rst
changed readme formatting
changed changelog to rst
fixed changelog formatting
fixed readme formatting
fixed slugs remaining lookup