OTHER: small fix to correctly connect Windows to the mainwindow after a showEvent

Previously a show event in PlaylistWindow and EqualizerWindow didn't connect
those windows to the Mainwindow

src/equalizer/equalizerwindow.cpp

@@ -53,6 +53,7 @@ EqualizerWindow::showEvent (QShowEvent *event)
 {
 	QSettings s;
 	s.setValue ("equalizer/visible", true);
+	m_mw->attachWidgets ();
 
 	emit visibilityChanged (true);
 }

src/playlist/playlistwindow.cpp

@@ -84,6 +84,7 @@ PlaylistWindow::showEvent (QShowEvent *event)
 {
 	QSettings s;
 	s.setValue ("playlist/visible", true);
+	m_mw->attachWidgets ();
 
 	emit visibilityChanged (true);
 }