GIR metadata: Fix out and ref parameters in GraphModel
Vapigen did not identify the out and ref parameter in the following methods:
public bool get_iter_first (out Dazzle.GraphModelIter iter);
public bool get_iter_last (out Dazzle.GraphModelIter iter);
public static GLib.Value iter_get_value (Dazzle.GraphModelIter iter, uint column);
public static bool iter_next (ref Dazzle.GraphModelIter iter);
This MR add rules for it to Dazzle-1.0.metadata