The parsing of light data from maps is now in the client library, and
basic light management is in scene. Putting the light loading code into
the Vulkan renderer was a mistake I've wanted to correct for a while.
The client code still needs a bit of cleanup, but the basics are working
nicely.
While there's currently only the one still, this will allow the entities
to be multiply queued for multi-pass rendering (eg, shadows). As the
avoidance of putting an entity in the same queue more than once relies
on the entity id, all entities now come from the scene (which is stored
in cl_world in the client code for nq and qw), thus the extensive
changes in the clients.
It holds the data for a basic 3d camera (transform, fov, near and far
clip). Not used yet as there is much work to be done in cleaning up the
client code.
