[WIP] Ground texture mod

[philip.ed]

Ali, that looks amazing!

Brilliant work! Whilst I can see what the others mean about earthing the terrain colours up, I don't think they need darkening. I think that a lot of the terrain tiles have colours which look quite acidic. Rather than working on the whole tile-set, maybe it's just these individual areas which need sorting out?

Either way, that really does look quite amazing. The trees darkness makes so much difference.