Fixes includes wrt opm-parser PR-656

Several files stopped compiling due to relying on opm-parser headers
doing includes. From opm-parser PR-656
https://github.com/OPM/opm-parser/pull/656 this assumption is no longer
valid.

opm/core/props/satfunc/RelpermDiagnostics.cpp

@@ -19,6 +19,8 @@
 
 #include <opm/core/props/satfunc/RelpermDiagnostics.hpp>
 #include <opm/material/fluidmatrixinteractions/EclEpsScalingPoints.hpp>
+#include <opm/parser/eclipse/EclipseState/Tables/Sof2Table.hpp>
+#include <opm/parser/eclipse/EclipseState/Tables/SgwfnTable.hpp>
 
 namespace Opm{
 

opm/core/props/satfunc/RelpermDiagnostics.hpp

@@ -40,6 +40,9 @@
 
 namespace Opm {
 
+    class Sof2Table;
+    class SgwfnTable;
+
     ///This class is intend to be a relpmer diganostics, to detect
     ///wrong input of relperm table and endpoints.
     class RelpermDiagnostics