CONFIG: adjustments to environment

- provide default WM_DIR if not already set, to improve robustness if a
  reduced environment is used

- add etc/ to WM_PROJECT_SITE search. This makes the site directory
  structure consistent with the OpenFOAM structure.
  Eg,

      WM_PROJECT_SITE/etc/..
      WM_PROJECT_SITE/bin/..
      WM_PROJECT_SITE/platforms/..

- Don't set/export WM_OSTYPE.  The default is POSIX and is properly
  defaulted throughout, including in CMakeLists-OpenFOAM.txt (also for
  Catalyst)

applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/Make/options

@@ -18,5 +18,5 @@ LIB_LIBS = \
     -lconversion \
     -lgenericPatchFields \
     -llagrangian \
-    -L$(FOAM_LIBBIN) -lfoamPv-pv$(PARAVIEW_MAJMIN) \
+    -L$(FOAM_LIBBIN) -lfoamPv-pv$(PARAVIEW_API) \
     $(GLIBS)

applications/utilities/postProcessing/graphics/PVReaders/vtkPVblockMesh/Make/options

@@ -12,5 +12,5 @@ EXE_INC = \
 LIB_LIBS = \
     -lmeshTools \
     -lblockMesh \
-    -L$(FOAM_LIBBIN) -lfoamPv-pv$(PARAVIEW_MAJMIN) \
+    -L$(FOAM_LIBBIN) -lfoamPv-pv$(PARAVIEW_API) \
     $(GLIBS)