gm kicks off game and dies
remove two gm states

gm handles many game simultaneously:
there is no need for states 'playing' or 'tournament'
move msg construction to sxml
don't restart dying rooms
fix startup for ttt
don't restart ttt's
export gm:next_player/2
room tracks gm and players connections

and notifies about crashes
minor fixes
don't check for inet:setopts return

handling of closed connection is done via {tcp_closed, Socket} message
fix bad return that crashed gen_server
do not double encode
WIP
fix 2 errors
gm: process error message
gm: use throw/catch flow for parsing and validation of xml
gm: use lager
gm: process game_over and next_player messages
turn on lager for gma
gm_client: use throw/catch flow for validation