Add geometry and parameter files for tof_v20b.

The geometry tof_v20b fixes an issue with tof_v20a found at 18.04.21. The number of chanels per module and also some module types were wrong. For consisteny reasons the existing geometry tof_v20a wasn't changed but a new fixed one tof_v20b was created. The macro used for the generation of the tof_v20 geometries was commited with 0a48b9fc. The complete disscusions about the new geometry are at !314 (merged) CbmSoft/cbmroot_geometry!83 (merged)