#3339 Make order of summary curves in plot predictable.

* The issue is sorting on pointer address for ensembles and summary cases. Instead sort by name.
* The crucial changes are in RiaSummaryCurveDefinition.cpp, RimSummaryCase and RimSummaryCaseCollection.
* The rest of the changes are just fallout from changing the pure virtual method RimSummaryCase::caseName to be const. The rest just follows.
* RimGridSummaryCase::caseName does alter something, but this variable was already declared mutable.

ApplicationCode/ProjectDataModel/Summary/RimSummaryCaseCollection.cpp

@@ -425,6 +425,14 @@ bool RimSummaryCaseCollection::validateEnsembleCases(const std::vector<RimSummar
     }
 }
 
+//--------------------------------------------------------------------------------------------------
+/// Sorting operator for sets and maps. Sorts by name.
+//--------------------------------------------------------------------------------------------------
+bool RimSummaryCaseCollection::operator<(const RimSummaryCaseCollection& rhs) const
+{
+    return name() < rhs.name();
+}
+
 //--------------------------------------------------------------------------------------------------
 ///
 //--------------------------------------------------------------------------------------------------