Correct RICH geometry v21a (#2425)
In the input repository many files for the media checks were added. In the geometry repository the rich geometry v21a was corrected. The geometry now has the correct name and the correct radiation length of the materials.
In the macro Import_GDML_Export_ROOT.c which is used to convert the GDML geometry into a ROOT geometry the following changes were done.
Use the correct TGeo unit system. Use TVolume->Export to store the RICH volume in the ROOT file. Add the correct placement matrix according to the shift of the coordinate system. Also create the file needed for the media check. Create all needed materials prior to the import from the gdml file such that they are properly exported to the ROOT file.