Overgrowth alpha 42

Here is what is new in Overgrowth in this weekly alpha. If you are confused what a weekly alpha is, or even what Overgrowth is, please read our fancy FAQ. Basically, we are developing a massive video game from the ground up -- we are able to do this completely independently by accepting preorders for the game before it's done!

Aubrey has made a number of new art assets this week, which are included in this alpha. On the coding front, here are a few highlights from the source repository:

- Added camera frustum culling for decals - Added a way for the UI to read/write persistent data - Added a way to take layered screenshots - Various UI updates - Fixed sun state saving - Bug fixes

Thanks as always for all the support! See you guys in IRC and the forums.