Added block to show the micropolygon grid. Changed default type of input normal to Complex Fresnel block, from vector to normal type. Changed environment block parameters, and the resulting output, which was aov_reflection - should be the block's $(value). Added LDR image expansion to environment block. Changed SHADEOP_PARAMETERS to environment block and tweaked some details. Fixed typos in LDR expansion function in texture header, and added float version of LDR expansion.
