Create a checkbox for every reftrack type so one can filter them

        :returns: None
        :rtype: None
        :raises: None

def setup_filter(self, ):
        """Create a checkbox for every reftrack type so one can filter them

        :returns: None
        :rtype: None
        :raises: None
        """
        types = self.refobjinter.types.keys()
        for i, t in enumerate(types):
            cb = QtGui.QCheckBox("%s" % t)
            cb.setChecked(True)
            cb.toggled.connect(self.update_filter)
            self.typecbmap[t] = cb
            self.typefilter_grid.addWidget(cb, int(i / 4), i % 4)