need to add tty parameter for juno branch

[spark]

add to add tty args on docker driver juno branch
 vi /usr/lib/python2.7/site-packages/novadocker/virt/docker/driver.py
    def spawn(self, context, instance, image_meta, injected_files,
              admin_password, network_info=None, block_device_info=None):
        image_name = self._get_image_name(context, instance, image_meta)
        args = {
            'hostname': instance['name'],
            'mem_limit': self._get_memory_limit_bytes(instance),
            'cpu_shares': self._get_cpu_shares(instance),
            'network_disabled': True,
            'tty': True,<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
        }