Strip rh valid fix

SiStripRecHitsValid:  Fix a bug that was disabling filling of histos for no. of recHits by subdet.  Adjust the binning of the now-enabled histograms.
  For matched recHits, limit the simHits projected from the stereo sensor to those actually on the stereo sensor.
TrackerHitAssociator:  For matched recHits, suppress ghost hits by requiring a simTrack association.
dynamic_casts can be expensive. Did you check there were no regressions performance wise?