Add a "username" field to players. Verify that all players with a username or email are registered
Add UI for inviting players to the game when creating one
Disambiguate the fields in a query
Properly maintain faction_info during faction selection
Select a primary email address
Normalize usernames in check_username_is_registered, return the primary email address
Document the recent changes
Fully evaluate and index the game right after creation, instead of waiting for first save()
Don't leak the full faction info through in save()

Necessary since the faction info can now contain information
that's not visible in the admin interface.