Blender Git Loki

Cycles: Fix wrong termination criteria in intersect_all functions

It was possible to miss bounces termination criteria in this functions,
mainly when max_hits was set to 0.

Made the check more robust in traversal functions (which should not
affect performance, it's an operation of same complexity AFAIK).

Also avoid doing ray-scene intersection from shadow_blocked when
limit of transparent bounces was already reached.