Add copyright to files missed in !328

Associators/Associators/options/MCParticleToMCHit.py

+###############################################################################
+# (c) Copyright 2000-2019 CERN for the benefit of the LHCb Collaboration      #
+#                                                                             #
+# This software is distributed under the terms of the GNU General Public      #
+# Licence version 3 (GPL Version 3), copied verbatim in the file "COPYING".   #
+#                                                                             #
+# In applying this licence, CERN does not waive the privileges and immunities #
+# granted to it by virtue of its status as an Intergovernmental Organization  #
+# or submit itself to any jurisdiction.                                       #
+###############################################################################
 # Options to initialize MCParticle to MCHit associators
 
 from Configurables import MCParticle2MCHitAlg, TrackerMCParticle2MCHitAlg, DataOnDemandSvc