Fixed messages complaining about no autorelease pool being set up with objects leaking on the Mac. I simply initialized an autorelease pool in the couple of places that needed it.

#include <QtGui/QApplication>
#include "mainwindow.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();
    return a.exec();
}