Updated to support django <=1.4
Support for username with extra chars.
Use time-zone aware datetimes if time zone support is enabled in Django 1.4
Added post_delete signal to Avatar model in order to clean up the file system when AVATAR_MAX_AVATARS_PER_USER is equal to 1 or when Avatar instances are removed.  This functionality is controlled by the new AVATAR_CLEAN_REMOVED setting which is False by default.
2.0a2-eldarion

Conflicts:

	setup.py
merged two 1.4 messages implementations
Add ability to use https with gravatar
Add testdata to distribution package so third parties can run the tests
Optional css_class passed as args to the avatar tag.

If no class is passed, no class is added.