WCSim Validation

3fdeb939e8fa7d3ceea30adb05abcb973dd1e2f7

Pull Request #558: separate tyvek reflectivities

IWCD_500MeVmum_centre_xdir

Tests
2834.38 sec
wcsimrootevent plot pass
wcsimrootevent2 plot pass
wcsimrootevent_OD plot pass
Geom pass
bad pass
Geometry warnings pass