Always delete disconnected sockets. (#658)
Always delete disconnected sockets. (#658)

Previously, sockets that belonged to a user that was logged in but was
not in a game were not being removed from the socket list.

Additionally, it isn't possible to send game state to a socket that has
been disconnected, and rooms are left automatically upon disconnection.
gryffon/ringteki,gryffon/ringteki,jeremylarner/ringteki,cryogen/gameteki,Antaiseito/throneteki_for_doomtown,ystros/throneteki,jeremylarner/ringteki,Antaiseito/throneteki_for_doomtown,samuellinde/throneteki,jbrz/throneteki,cryogen/throneteki,DukeTax/throneteki,DukeTax/throneteki,jbrz/throneteki,cryogen/gameteki,jeremylarner/ringteki,samuellinde/throneteki,gryffon/ringteki,cryogen/throneteki