Galactic Core v1.2

- Update: Smaller file size
- New Feature: Touch sensitive camera movement

A couple times now, I've tried reducing the background texture's filesize by changing it to a JPG.  The problem is, JPG images rendered to the screen result in a pretty horrible moire pattern as they get rotated (a side effect of the compression, I think, because it's not there at all for PNG).

After a couple of failed attempts I discovered that Gimp's JPG exporter lets you control which style of subsampling is used, an option I don't think I've ever seen in a JPG options menu before.  Switching to 1x1 subsampling largely fixed the moire issue, and allowed the image size to drop by almost 700k.  I'll call that a win.

The other meaningful change is touch sensitivity.  If you enable this in the prefs, the camera position will move based on where you touch the screen.  I tried to keep this relatively slow and non-crazy, in keeping with the philosophy of the wallpaper being a backdrop and not a toy.