Remove trailing spaces.
Fix except syntax.
Add compat module that stores unicode/str fixes mixin.
Add __future__ imports for unicode_literals and absolute_import
Remove wrong usage of super call.
Fix unicode handling and remove usage of python3 dropped methods.
Fix tests.
fix "argument 2 must be str, not unicode" on python 2.6 and python 2.7
test python 3.3 on travis
updated requirements.txt to fix python3 on travis-ci
Merge pull request #15 from djangonauts/python3

Added Python3 support