Split classes in RigStatisticsCalculator.h/.cpp into separate files

New files:RigNativeStatCalc.h./cpp, RigMultipleDatasetStatCalc.h/.cpp.,
in addition to RigStatisticsCalculator.h/.cpp.

ApplicationCode/ReservoirDataModel/RigNativeStatCalc.h

@@ -0,0 +1,49 @@
+/////////////////////////////////////////////////////////////////////////////////
+//
+//  Copyright (C) Statoil ASA
+//  Copyright (C) Ceetron Solutions AS
+// 
+//  ResInsight is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+// 
+//  ResInsight is distributed in the hope that it will be useful, but WITHOUT ANY
+//  WARRANTY; without even the implied warranty of MERCHANTABILITY or
+//  FITNESS FOR A PARTICULAR PURPOSE.
+// 
+//  See the GNU General Public License at <http://www.gnu.org/licenses/gpl.html> 
+//  for more details.
+//
+/////////////////////////////////////////////////////////////////////////////////
+
+#pragma once
+
+#include "RigStatisticsCalculator.h"
+
+#include "cvfBase.h"
+#include "cvfObject.h"
+#include "cvfCollection.h"
+
+class RigHistogramCalculator;
+class RigCaseCellResultsData;
+
+//==================================================================================================
+/// 
+//==================================================================================================
+class RigNativeStatCalc : public RigStatisticsCalculator
+{
+public:
+    RigNativeStatCalc(RigCaseCellResultsData* cellResultsData, size_t scalarResultIndex);
+
+	virtual void minMaxCellScalarValues(size_t timeStepIndex, double& min, double& max);
+	virtual void posNegClosestToZero(size_t timeStepIndex, double& pos, double& neg);
+	virtual void valueSumAndSampleCount(double& valueSum, size_t& sampleCount);
+
+	virtual void addDataToHistogramCalculator(RigHistogramCalculator& histogramCalculator);
+    virtual size_t  timeStepCount();
+
+private:
+	RigCaseCellResultsData* m_resultsData;
+    size_t m_scalarResultIndex;
+};