Fix UI rendering to not use the bouncegrid texture; it looked interesting on the...

Fix UI rendering to not use the bouncegrid texture; it looked interesting on the console text but was definitely a bug - now tracks a ui parameter on several surface drawing functions, and triggers the notrippy path in the material rendering as one wouldn't want r_trippy affecting UI either.

Fix a bug that caused bouncegrid to render black if any light was culled by traces (return that was supposed to be a continue).

Changed default values for these cvars to make bouncegrid emphasize the bounced light more, but also reduce the intensity:
r_shadow_bouncegrid_dynamic_directionalshading : 0 -> 1
r_shadow_bouncegrid_dynamic_lightradiusscale : 2 -> 5
r_shadow_bouncegrid_dynamic_maxbounce : 2 -> 5
r_shadow_bouncegrid_static_lightradiusscale 2 -> 5
r_shadow_bouncegrid_intensity 4 -> 1

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@12490 d7cf8633-e32d-0410-b094-e92efae38249