Fix to prevent premature game end
- This would previously occur when a beta either creates or joins another 2nd game even though she wasn't in the 1st
Fixed logic that detected whether or not it was ok to force end a game
- also fixed bug where only one player was notified of a game having been force-ended
Comments cleanup
- There were concerns about some async db ops related to _endGameFromPlayerExit. But because the documents getting updated are different from the docs updated in _endGameFromPlayerExit, we should actually be ok.
Merge pull request #211 from jonuy/endgamefrominvite

_endGameFromInvite fixes