code: private void overlayRightShift(
      int           ix)
    {
      for (int j = ix; j > 0; j--)
        _nodeKey[j] = _nodeKey[j-1];
    }
docs: Overlay a key to be deleted by moving keys right.
  
  <p>We are removing a key from a node.  We shift all of the keys
  right to overlay the slot of the key to be deleted and open up the
  slot occupied by the left most key in the node.</p>