WCSim Validation

d98e372eaacd7797a0ac8620c9ed1437e8419e7d

Pull Request #520: Update LI code, better sampling

HKFD_5MeVem_centre_xdir

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