This fixes the segfault and pushes things very much in the desired
direction of proper system independence for rendering and presentation
separation (though things were headed in the right direction before).
This fixes the status bar refresh issues in sw. The problem was that with
two viddef's hanging around, things got a little confused and recalc_refdef
wasn't getting into the renderer.
This allows the vid module to load the render module and access render
specific functions before the renderer initializes, which happens to need
an initialized vid module...
The renderer now gets initialized and things sort of work (qw-client will
idle, though nothing is displayed). However, as the viddef stuff is broken,
it segs on trying to run the overkill demo.