[MVP] Team mode

[vintage]

Allow players to define teams in order to provide some kind of competition - gather points for your team and at the end see who got more of these.

TODO:

• Allow to define two teams (blue/red?) with up to 5 players each (list of names)
• When the category finishes the game needs to inform whose turn is next. John (red) -> Alice (blue) -> Bob (red) -> ...
• Game score screen needs to provide some mechanism to swap correctness of answers (due to invalid tap, or race-condition timeout)
• Points after each category needs to be added to the team summary
• When every player from each team passed his turn, show teams summary (points) and which team won the competition