start Collapsed Commissioner

        Returns:
            True: successful to start Commissioner
            False: fail to start Commissioner

def startCollapsedCommissioner(self):
        """start Collapsed Commissioner

        Returns:
            True: successful to start Commissioner
            False: fail to start Commissioner
        """
        print '%s call startCollapsedCommissioner' % self.port
        if self.__startOpenThread():
            time.sleep(20)
            cmd = 'commissioner start'
            print cmd
            if self.__sendCommand(cmd)[0] == 'Done':
                self.isActiveCommissioner = True
                time.sleep(20) # time for petition process
                return True
        return False