add first version of a filter handle

Following the discussion at the AMG meeting last week I added a first version of a filter handle. For now this does nothing more than wrap the corresponding member function of the algorithm class, but once people are happy and we put this is in, we can add code like we have in AthFilterAlgorithm to report to the cut flow service, and provide a systematics-aware version of this handle. I also switched GRLSelectorAlg to use this, so that we have one example, plus that algorithm ought to be using this handle.

I named this EL::AnaFilterHandle and placed it inside the AnaAlgorithm package. Not sure if people are happy with either the location or the name, but I'm not particularly attached to either and we could easily change that.

Tagging the usual suspects: @tadej @jburr @akraszna @lheinric @alister

Let's also add @ssnyder and @leggett, in case they have any concerns with this class making it into offline code at some point.

DataQuality/GoodRunsLists/GoodRunsLists/GRLSelectorAlg.h

@@ -6,6 +6,7 @@
 #define GOODRUNSLISTS_GRLSELECTORALG_H 1
 
 #include <AnaAlgorithm/AnaAlgorithm.h>
+#include <AnaAlgorithm/FilterReporterParams.h>
 #include <AsgTools/ToolHandle.h> //included under assumption you'll want to use some tools! Remove if you don't!
 
 #include "AsgAnalysisInterfaces/IGoodRunsListSelectionTool.h"
@@ -28,6 +29,7 @@ class GRLSelectorAlg: public EL::AnaAlgorithm {
 
  private: 
   ToolHandle<IGoodRunsListSelectionTool> m_grlTool;
+  EL::FilterReporterParams m_filterParams {this};
   int m_passed = 0;
   int m_total = 0;