BUG: Fix uniqueOrder() to not drop largest item

Fixes http://www.openfoam.com/mantisbt/view.php?id=330

src/OpenFOAM/containers/Lists/ListOps/ListOpsTemplates.C

@@ -243,6 +243,7 @@ void Foam::uniqueOrder
                 order[n++] = order[i];
             }
         }
+        order[n++] = order[order.size()-1];
         order.setSize(n);
     }
 }