Probably not the most efficient implementation, but works.
Issues:
* Doesn't seem to render until the second frame. No clue why, yet.
* Hardcoded 640x480 in more places.
* Creates new FBOs for every subpass every frame. Should be done at Framebuffer build or CommandBuffer build time.
This directory used to contain both the state tracking code for the
backends, and the common utilities that could be used both by the
backends and the rest of the code. Things are now:
- src/common is utility code for the whole repo
- src/backend contains libNXT's code
- src/utils is utility code that we don't want in libNXT
This commit also changes all includes to use global paths from src/
bacause it had to touch a bunch of #include statements anyway.