Add Omegacc and Omegabc with their anti particles
I have added 4 files, Omegacc and Omegabc with their anti particles,*.cpp and *.h. I have also updated the GiGaPhysUnknownParticles.cpp file by adding these 4 files in place.
Closes LHCBGAUSS-1490
Edited by Gloria Corti