Draft: Move Particle2MCTruth to Rec

The classes in this package are used in BTagging and MCTruthAndBkgCatAlg.cpp which are both in Rec. It doesn't make sense to have Particle2MCTruth in Analysis.

Phys/Particle2MCTruth/dict/Particle2MCTruthDict.h

-/*****************************************************************************\
-* (c) Copyright 2000-2018 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".   *
-*                                                                             *
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-* granted to it by virtue of its status as an Intergovernmental Organization  *
-* or submit itself to any jurisdiction.                                       *
-\*****************************************************************************/
-#ifndef DICT_PARTICLE2MCTRUTHDICT_H
-#  define DICT_PARTICLE2MCTRUTHDICT_H 1
-
-// Include files
-
-/** @file dict/Particle2MCTruthDict.h
- *
- *
- *  @author Juan PALACIOS
- *  @date   2009-03-10
- */
-#  include "P2MCP/IP2MCP.h"
-#  include "P2MCP/P2MCPTypes.h"
-#endif // DICT_PARTICLE2MCTRUTHDICT_H
-
-namespace {
-  std::vector<LHCb::MCParticle::ConstVector> __stdvector_mcpVC;
-}