Changeset 8557 for branches/HeuristicLab.EvolutionaryTracking/HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/Interfaces/Operators/ITracingSymbolicExpressionTreeOperator.cs

#1772: Introduced base class and interface for tracing operators. Introduced SymbolicExpressionTreeNodeComparer interface to be implemented by node matching operators. Fixed bug in the TracingSymbolicExpressionTreeManipulator where nodes modified by the Full- and OnePoint tree shakers were not correctly detected. The SymbolicExpressionTreeNodeSimilarityComparer is now injected in the tracing genetic operators as a parameter.