ENH: additional PtrList constructor and memory management method

- PtrList::release() method.

  Similar to autoPtr and unique_ptr and clearer in purpose than
  using set(i,nullptr)

- Construct from List of pointers, taking ownership.

  Useful when upgrading code. Eg,

     List<polyPatch*> oldList = ...;
     PtrList<polyPatch> newList(oldList);
     ...

BUG: incorrect resizing method names (PtrDynList) in previously unused code

src/OpenFOAM/db/functionObjects/functionObjectList/functionObjectList.C

@@ -103,7 +103,7 @@ Foam::autoPtr<Foam::functionObject> Foam::functionObjectList::remove
         oldIndex = *iter;
 
         // Remove pointer from the old list
-        oldptr = this->set(oldIndex, nullptr);
+        oldptr = this->release(oldIndex);
         indices_.erase(iter);
     }
     else