ENH: remove reliance on the Xfer class (issue #639)

This class is largely a pre-C++11 holdover. It is now possible to
simply use move construct/assignment directly.

In a few rare cases (eg, polyMesh::resetPrimitives) it has been
replaced by an autoPtr.

applications/utilities/preProcessing/viewFactorsGen/viewFactorsGen.C

@@ -865,7 +865,7 @@ int main(int argc, char *argv[])
             IOobject::NO_WRITE,
             false
         ),
-        globalFaceFaces
+        std::move(globalFaceFaces)
     );
     IOglobalFaceFaces.write();
 
@@ -881,7 +881,7 @@ int main(int argc, char *argv[])
             IOobject::NO_WRITE,
             false
         ),
-        visibleFaceFaces
+        std::move(visibleFaceFaces)
     );
     IOvisibleFaceFaces.write();
 
@@ -895,7 +895,7 @@ int main(int argc, char *argv[])
             IOobject::NO_READ,
             IOobject::AUTO_WRITE
         ),
-        map.xfer()
+        std::move(map)
     );
 
     IOmapDist.write();