Shrimp Shader Generator FLTK2 GUI (SVN)

Added a note about the INIT_AOV_PARAMETERS macro in shadingmodels. Removed topolar2d() from shrimp_helpers, and created an header for coordinates conversions, as well as its respective blocks. Updated the Voronoi (Karlsruhe/Moscow metric) diagram block to use the new coordinate conversion. Updated the rt_environment scene (it was using some xml from older blocks).