Implement multi-region PVT for all property classes

since they are not using a single PVT table anymore, their "Single"
prefix has been removed...

opm/core/props/pvt/PvtPropertiesIncompFromDeck.cpp

@@ -35,7 +35,7 @@ namespace Opm
 
     void PvtPropertiesIncompFromDeck::init(Opm::DeckConstPtr deck )
     {
-        // If we need multiple regions, this class and the SinglePvt* classes must change.
+        // If we need multiple regions, this class and the Pvt* classes must change.
         int region_number = 0;
 
         PhaseUsage phase_usage = phaseUsageFromDeck(deck);

tests/liveoil.DATA

@@ -9,6 +9,19 @@ WATER
 
 FIELD
 
+-- tests for the PVT functions need a grid because the OPM-API for the
+-- PVT functions assumes the presence of compressed grid cells,
+-- i.e. we need to be able to map from compressed to logical cartesian
+-- cell indices to find out the PVT region of a cell
+DIMENS
+3 3 3 /
+DXV
+1 2 3 /
+DYV
+1 2 3 /
+DZV
+1 2 3 /
+
 PVTO
 --     Rs       Pbub       Bo        Vo
       .0         14.7     1.0000     1.20  /

tests/wetgas.DATA

@@ -9,6 +9,19 @@ GAS
 
 FIELD
 
+-- tests for the PVT functions need a grid because the OPM-API for the
+-- PVT functions assumes the presence of compressed grid cells,
+-- i.e. we need to be able to map from compressed to logical cartesian
+-- cell indices to find out the PVT region of a cell
+DIMENS
+3 3 3 /
+DXV
+1 2 3 /
+DYV
+1 2 3 /
+DZV
+1 2 3 /
+
 -- PVT PROPERTIES OF DRY GAS (NO VAPOURISED OIL)
 -- FROM SPE3 Blackoil Kleppe
 --