I don't remember why I kept the abbreviated configs for images and image
views, but it because such that I need to be able to specify them
completely. In addition, image views support external images.
The rest was just cleaning up after the changes to qfv_resobj_t.
Partial because frame buffer creation isn't handled yet (using six
layers), but using layer a layer capable view and shaders doesn't cause
problems (other than maybe slightly slower code).
I had debated putting the blending in the compose subpass or a separate
pass but went with the separate pass originally, but it turns out that
removing the separate pass gains 1-3% (5-15/545 fps in a timedemo of
demo1).
It's a bit flaky for particles, especially at higher frame rates, but
that's due to supporting only 64 overlapping pixels. A reasonable
solution is probably switching to a priority heap for the "sort" and
upping the limit.
