WCSim Validation

3a1c0750d087218ed768ba122b8e92a8e9f1787a

Pull Request #543: assign correct thicknesses to FDOD WLS plates

SK_500MeVem_centre_xdir

Tests
3166.88 sec
wcsimrootevent plot pass
wcsimrootevent2 plot pass
wcsimrootevent_OD plot pass
Geom pass
bad pass
Geometry warnings pass