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In a few rare cases (eg, polyMesh::resetPrimitives) it has been
replaced by an autoPtr.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/test/mapDistributePolyMesh/Test-mapDistributePolyMesh.C

@@ -51,19 +51,20 @@ int main(int argc, char *argv[])
     const scalar instanceValue(0.005);
 
 
-    IOobject io
+    IOmapDistributePolyMesh map
     (
-        "procAddressing",
-        instance,
-        fvMesh::meshSubDir,
-        mesh,
-        IOobject::MUST_READ,
-        IOobject::NO_WRITE,
-        false
+        IOobject
+        (
+            "procAddressing",
+            instance,
+            fvMesh::meshSubDir,
+            mesh,
+            IOobject::MUST_READ,
+            IOobject::NO_WRITE,
+            false
+        )
     );
 
-    IOmapDistributePolyMesh map(io);
-
     {
         // Load the instance mesh
         runTime.setTime(instanceValue, 0);
@@ -112,7 +113,6 @@ int main(int argc, char *argv[])
             }
         }
 
-
         {
             const mapDistribute& cellMap = map.cellMap();
             pointField cc(mesh.cellCentres());