GCOM Windows game

The idea is to get an friends-and-family beta together first, then strip that down to a minimal public-facing demo.

As a brief summary of what's needed before that can happen:-
- a little bit more PC customisation (particularly a better interface for setting custom names)
- more terrain pieces for the random map generator
- more research lines, partly to add a bit more variety, partly to push some of the more powerful stuff down the tree
- (hidden fun stuff) to end the first chapter
- encryption of assets
- an actual installer

My like-to-haves for the demo:-
- audio
- some documentation of the tileset config files
- working UI config files
- a tidyup of the skirmish editor, perhaps add a defence mode with scoring for fun
- reformat my existing tutorials into something less slipshod

Not a huge amount compared to the work so far, so let's see how it goes.