Improve the game/playerstat model relationship
- WARNING: migrations DO NOT PRESERVE past game data!
- change game to depend on teamstat rather than team
- change playerstat to depend on teamstat rather than team
- move team finder(fetch_teams_by_name_for_league_as_array) from Team to Teamstat
- upate game model (which sucks). remove teamstat_for_league. No longer needed
- new game decorator
game controller spec, only call create once for user
fix a long time broken game controller spec