title: Update QWidget every minutes
body: <p>Is their a way possible to update a Qwidget in PyQT4 every  15 minutes ? I know their is something like a Qtimer but is it also possible to make a QWidget update itself at a specific time,for example 00h00 00h15 00h30 00h45 01h00,... . So is their a way to make the Qtimer depend on the time? </p>