create a lobby gamestate

[NimbusBP1729]

@jessehorne I'm still trucking along with this project, but you were right about the server issues.

Hawkthorne's Lua code is terribly inefficient and it's causing real networking problems. I want to roll out a version of multiplayer really soon, but I have to develop some client-side gamestates(in Lua!!!!)

As it turns out the Lua client is much thicker than the java one. The libgdx/java one is primitive mainly because I haven't had the time to load all images and create a bunch of gamestates, but we already have that in Lua