Implenent file_save and file_save_as

This allows us to do the right thing at exit (and also connects to more of
the menu actions to actually do something).

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-ui/mainwindow.h

@@ -94,6 +94,8 @@ private:
 	void readSettings();
 	void writeSettings();
 	void redrawProfile();
+	void file_save();
+	void file_save_as();
 };
 
 MainWindow *mainWindow();