add Procfile
renameming models to go well with django permissions

Permissions.name can have up 50 chars
update admin
update data loading script
update version in docstring
Merge branch 'version_0.5'

Update staff to work with postgres - shorten model names to fit django's
50 chars in permission model name.

Add heroku Procfile.
Improve project structure

Move example project to separate directory. Add setup.py to install
kitabu.