Background class

I've now abstracted the background (area) into its own class so each arena can handle it's specialised drawing routine, whether it be animating water, falling leaves, rain, all that cool stuff. Later on once I've drawn and done all the backgrounds then I will go and paint them properly and animate them to make them come to life.

First things first though, I am going to be implementing the proper Health bar and then work on COM/AI stuff, which is about half done (the difficult half ;)) including the AI insight/readout panel.