Better random laser casting. Now averages the samples and correctly scales them.

...s/optical_bench/src/Optix Files/glass_iterative_camera.cu

demos/optical_bench/src/Optix Files/laser_caster.cu

demos/optical_bench/src/Optix Files/laser_target_material.cu

demos/optical_bench/src/Optix Files/normal_shader_new.cu

demos/optical_bench/src/Optix Files/prd.h

demos/optical_bench/src/laser_menu.cpp

demos/optical_bench/src/optix_context_manager.cpp

demos/optical_bench/src/ray_pass.cpp

demos/optical_bench/src/ray_pass.hpp