add timezone support to invite and fallback to normal datetime
moved datetime import to utils.py
changed datetime from utils to compatible datetime. need to do this to access timedelta function in original datetime package
add timezone aware to model_managers
importing timedelta directly from original datetime and using timezone aware in models
use of dateutil if present. if not, it falls back to normal datetime
Merge pull request #253 from duduklein/timezone-aware

Timezone aware
pep8
Add middleware for canvas apps:
add memcache to development requirements, otherwise tests fail with ImportError: No module named memcache
add middleware for canvas
if referer not facebook, we pass
add error denied detection
redirect user when app not authorized
connecting user when permissions are given
add verification for same user
checking for permisions
changed behavior for error in order to reauthenticate
made pep8 complaint
bump
added support to show the error code, making error mapping easier
moving django_facebook/views to always require post
max length on username, first_name and last_name should fix #258
added setting for profile image path, fixes #261
Merge pull request #256 from duduklein/facebook-canvas

Add middleware for canvas apps:
cleanup
bumping up the version
renamed
renmaed middlewares
implemented partially the changes suggested in pull 226
missing file