TrkVertexFitterValidation[Tools,Interfaces]: delete unused packages

Delete unused TrkVertexFitterValidationTools and TrkVertexFitterValidationInterfaces packages. The code has not seen any relevant updates in a long time and packages are not referenced anywhere in the release.

@sroe, @goetz, please object if this is still in use.

Tracking/TrkValidation/TrkVertexFitterValidationInterfaces/TrkVertexFitterValidationInterfaces/IMcEventNtupleTool.h

-/*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
-*/
-
-////////////////////////////////////////////////////////////////////////////////
-//    IMcEventNtupleTool.h
-//   Header file for interface of McEventNtupleTools
-//////////////////////////////////////////////////////////////////////////////
-// (c) ATLAS Detector software
-/////////////////////////////////////////////////////////////////////////////
-// Tatjana.Lenz@cern.ch
-////////////////////////////////////////////////////////////////////////////
-
-#ifndef TRK_IMCEVENTNTUPLETOOL_H
-#define TRK_IMCEVENTNTUPLETOOL_H
-
-#include "GaudiKernel/IAlgTool.h"
-#include "AtlasHepMC/GenEvent.h"
-
-namespace Trk {
-static const InterfaceID IID_IMcEventNtupleTool("IMcEventNtupleTool",1,0);
-
-
-/** @class IMcEventNtupleTool
-    provides the interface for validation tools which write special information
-    about MC particles & vertices into ntuples.
-*/
-
-class IMcEventNtupleTool : virtual public IAlgTool {
-public:
-     /**Interface ID, declared here, and defined below*/
-    static const InterfaceID& interfaceID();
-
-    /** fill and write ntuple data of a given VxCandidate */
-    virtual StatusCode fillMcEventData(const HepMC::GenEvent&) const = 0;
-};
-
-inline const InterfaceID& Trk::IMcEventNtupleTool::interfaceID() {
-    return IID_IMcEventNtupleTool;
-}
-
-} // end of namespace
-
-#endif // TRK_IMCEVENTNTUPLETOOL_H