Add translucent code
Add some function prototypes to mcintegrator.h from 'liyong' project.
Add BSDF_TRANSLUCENT  type to material.h
Update some functions in translucent.cc to actual  YafaRay core.
Add photonkdtree.h header file for some translucent.cc functions.
Note: review and compare to pkdtree.h for a possible merge in one file.
Add some functions for SSS to mcintegrator.cc and photon.cc
Add 'translucent' project to CMakeLists.txt
Integrate SSS code in directlight.cc, pathtracer.cc and photonintegr.cc
Add aligned definitions for MinGw compilers
Uncomment virtual destructor for translucenMat.
Comment unused code for fix some builds warning in photonintegr.cc
Uncomment virtual destructor for pathIntegrator_t. Useful for destorySSSMaps function.