(Blocked on #110) Demo: displays save icons

[abaire]

Super ugly proof of concept to show how we could display save game icons for XBEs (at least retail XBEs will likely have them, and I've seen at least a couple homebrew ones w/ them as well).

For clarity: This is both ugly from a UI perspective and terrible from a coding perspective and not actually intended to be merged, more to justify #124. A real implementation should have some actual though go into the user experience, and at least cache the decompressed images (right now they're recreated every frame and we're already running at low FPS). I also think the NV hardware should be able to display these DXT1 compressed images natively so maybe we wouldn't have to decompress them at all after the move to HW-accelerated rendering.