Improve cube shadow map resolution heuristics

Improve cube shadow map resolution determination by adjusting
for the window width and using a higher resolution when the
viewpoint is within the light volume. There is still potential
for better heuristics.

Signed-off-by: Harm Hanemaaijer <fgenfb@yahoo.com>
Fix SIMD bug in AABB intersection test

Fix a subtle bug in the SIMD-optimized version of the
CompletelyInside test between two AABBs. This resolves the problem
with octree creation because of which most objects ended up in the
root node.

Signed-off-by: Harm Hanemaaijer <fgenfb@yahoo.com>