Improve handling of external smesh

+ add SMESH_version.h.cmake to set full version number instead of using compiler define
+ do not set include path of smesh globally
+ do not set library path of smesh globally
+ do not set HAVE_NETGEN define globally
+ improve using debug and release libs of smesh for MSVC

src/Mod/Fem/App/FemMeshPyImp.cpp

@@ -37,9 +37,7 @@
 #include <SMDSAbs_ElementType.hxx>
 #include <SMDS_MeshElement.hxx>
 #include <SMDS_VolumeTool.hxx>
-#if SMESH_VERSION_MAJOR >= 7
-    #include <SMESHDS_Mesh.hxx>
-#endif
+#include <SMESHDS_Mesh.hxx>
 
 #include <TopoDS_Shape.hxx>
 #include <TopoDS_Face.hxx>