Menu refactoring and map reformatting

More menus! It's almost the same as the last gif, with some important differences (not least of which is the doubled frame rate).

The bottom left 'GOLD' panel is the same type as the three small submenus. The difference is the character rendering delay. GOLD is zero, and the little ones are progressively longer.

That was easy to implement thanks to having refactored the basic UI panel stuff out into its own class and having all of the actual rendered panels as subclasses that have their configuration passed in (via JSON parsed further up the chain, either from a local file or the server).

Another one that I actually forgot I hadn't mentioned is that I switched the map format around to make it a lot easier to process. Which had the (intended) side effect of making walls much easier to fill in given an initial map of just walkable floor tiles. So you can see the walls there. The only thing I haven't done yet is inner corners, which I think will be a bit more of a hassle, but not too much. There's probably a trick I'm missing... meh. I'll figure it out.

There are more tweaks and improvements to make, but now that the fundamental refactoring is done, I think it's battle UI time. Which means handling parties and turning a party of units into UI elements. Smiley