Added a completely new GUI.

Important internal changes:
* Most GUI callbacks are now methods of their HudSystems (cleans the code, mostly)
* Saving/Loading has been disconnected from GUI for now, since we need to redesign how save/loading works anyway.
* CEGUIWindow now supports animations (which are used slightly)
* A small change to microbe.lua, adding a species name. This is temporary, as the entire data-passing system needs to be changed (see #240)

See #130