Initial cut at game server.

Functional operations:
Kick player, create new game, add player to game, set player color and variant,
set player stats

Need to add "Get players in room" operation.
Need to return data in a sensible format.
Need to switch build system to rebar and add build scripts.
Adds rebar build script and server starter.
Adds super-basic Makefile.
JSON processing, 501 on unsupported method, implements getplayersinroom.
Moves server directory to erl_server.