This puts the hierarchy (transform) reference, animation, visibility,
renderer, active, and old_origin data in separate components. There are
a few bugs (crashes on grenade explosions in gl/glsl/vulkan, immediately
in sw, reasons known, missing brush models in vulkan).
While quake doesn't really need an ECS, the direction I want to take QF
does, and it does seem to have improved memory bandwidth a little
(uncertain). However, there's a lot more work to go (especially fixing
the above bugs), but this seems to be a good start.
Finally. I never liked it (felt bad adding it in the first place), and
it has caused confusion with function and global variable names, but it
did let me get the render plugins working.
Getting close to understanding (again) how it all works. I only just
barely understood when I got vulkan's renderer running, but I really
need to understand for when I modify things for shadows. The main thing
hurdle was tinst, but that was dealt with in the previous commit, and
now it's just sorting out the mess of elechains and elementss.
The entire vertex set from every model is put into one list (not yet
uploaded). chains of elements arrays are build for non-instanced models
(instanced models will have their chains built each frame).
Still nothing being rendered: still in the process of building the display
lists, but I'm making good progress. Get this into git before something
goes wrong :)
