- Add module that deals with different kinds of buffers (memory and external),
their allocation and usage for rendering. Also try to properly support modifiers this time.
- Describe gbm functionality as an allocator (instead of a rendering device/surface).
- Also create a quick-and-dirty dumb buffer allocator for tesing / simpler tasks.
- Add a (current untested) wrapper for dmabufs and some code for converting from gbm for now.
- (also untested) Swapchain helper to manage front/backbuffers for surfaceless rendering.