add Team model. Replaces Rank, with a many to many relation with User
use unicode instead of str
don't rely on team pk in tests
use Django 1.6 structure for tests
get rid of the unused sites framework
use users instead of teams in the game announcement form
add tests for the new teams behaviour
replace assertEquals by assertEqual in tests to suppress deprecation warnings
move factories.py to the tests directory
use same return type in TeamManager.get_or_create_from_players than in get_or_create
add tests on team users, not only teams count
add tests for team overlap
don't use assertItemsEqual since it's not available in Python 3
Merge remote-tracking branch 'origin/team'

Conflicts:
	game/models.py