Handle missing games in URLs

[devstopfix]

Right now we error:

14:40:27.173 [error] Ranch listener :elixoids_http had connection process started with :cowboy_clear:start_link/4 at #PID<0.551.0> exit with reason: {:noproc, {GenServer, :call, [{:via, Registry, {Registry.Elixoids.Games, {1}}}, {:spawn_player, "MCE"}, 5000]}}

Change to a case:

{:ok, _} = Registry.register(Registry.Elixoids.News, key(game_id), true)

[devstopfix]

Not a problem - ranch traps the exit and kills the websocket