start OpenThread stack

        Returns:
            True: successful to start OpenThread stack and thread interface up
            False: fail to start OpenThread stack

def __startOpenThread(self):
        """start OpenThread stack

        Returns:
            True: successful to start OpenThread stack and thread interface up
            False: fail to start OpenThread stack
        """
        print 'call startOpenThread'
        try:
            if self.hasActiveDatasetToCommit:
                if self.__sendCommand('dataset commit active')[0] != 'Done':
                    raise Exception('failed to commit active dataset')
                else:
                    self.hasActiveDatasetToCommit = False

            # restore whitelist/blacklist address filter mode if rejoin after reset
            if self.isPowerDown:
                if self._addressfilterMode == 'whitelist':
                    if self.__setAddressfilterMode('whitelist'):
                        for addr in self._addressfilterSet:
                            self.addAllowMAC(addr)
                elif self._addressfilterMode == 'blacklist':
                    if self.__setAddressfilterMode('blacklist'):
                        for addr in self._addressfilterSet:
                            self.addBlockedMAC(addr)

            if self.deviceRole in [Thread_Device_Role.Leader, Thread_Device_Role.Router, Thread_Device_Role.REED]:
                self.__setRouterSelectionJitter(1)

            if self.__sendCommand('ifconfig up')[0] == 'Done':
                if self.__sendCommand('thread start')[0] == 'Done':
                    self.isPowerDown = False
                    return True
            else:
                return False
        except Exception, e:
            ModuleHelper.WriteIntoDebugLogger("startOpenThread() Error: " + str(e))