[Starts #42398959] Enables creating and listing games
Adds datetime picker when creating new games

[Starts #41492225] The previous pivotal id was wrong. This one starts
the correct feature.
Adds datepicker to both start and enddate
Adds state-labels to games
Introduce game edit action
Adds show game action
Sorting games by starting date
Merge pull request #21 from ekampp/features/create_game_session

[Completes #41492225] Enables managing games and game sessions.