/// Updates the label and the references to it.
/// Will also handle undo/redo if \p cursor is passed.
void updateLabelAndRefs(docstring const & new_label, Cursor * cursor = 0);
/// Updates the label and the references to it.
/// Will also handle undo/redo if \p cursor is passed.
void updateLabelAndRefs(docstring const & new_label, Cursor * cursor = 0);