Implement new Region Selector conditions algorithm and flesh out the new RegSelTool class

The new approach to provide an individual RegSelTool for each subdetector makes use of the detector cabling information becoming conditions data.

The new RegSelCondAlg is a conditions algorithm that depends - in the first instance - on the pixel cabling conditions data, as a proof of concept, and adds the RS lookup table as conditions data.

The new RegSelTool that has a dependence on the RS lookup table conditions data. This is all to effectively replicate the Run 2 begin run functionality but with the new conditions handling in MT.

A subsequent request consisting of the configuration code needed to use these classes is currently being developed.

This is a first proof of principle implementation - once it is all working correctly any remaining issues will be fixed - remove redundant comments, add tables for other detector subcomponents etc, rather than allow these issues to act as a distraction at this point.

DetectorDescription/IRegionSelector/IRegionSelector/RegSelCondData.h

+/* emacs: this is -*- c++ -*- */
+/**
+ **   @file    RegSelCondData.h        
+ **                   
+ **            generic wrapper class for RegionSelector (or any)  
+ **            class, so we can keep the actual classes pure, 
+ **            and free from the predations of athena code
+ **
+ **   @author  sutt
+ **   @date    Tue  4 Feb 2020 15:25:00 CET
+ **
+ **   $Id: RegSelCondData.h, v0.0   Tue  4 Feb 2020 15:25:00 CET sutt $
+ **
+ **   Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
+ **/
+
+#ifndef  REGSELCONDDATA_H
+#define  REGSELCONDDATA_H
+
+#include <iostream>
+
+
+template<typename T>
+class RegSelCondData {
+
+public:
+
+  RegSelCondData( const T& t ) : m_payload(t) { } 
+
+  virtual ~RegSelCondData() { } 
+
+  const T* payload() const { return &m_payload; } /// could return the actual payload reference, but have everything using pointers 
+ 
+protected:
+
+  T m_payload;
+
+};
+
+
+template<typename T> 
+inline std::ostream& operator<<( std::ostream& s, const RegSelCondData<T>& r ) { 
+  return s << *(r->payload());
+}
+
+
+#endif  // REGSELCONDDATA_H 
+