Runner multi proc in 0.8.0

[Tezirg]

grid2op.Runner has broken multi processor execution in 0.8.0:

from grid2op import make
from grid2op.Runner import Runner
from grid2op.Agent import DoNothingAgent

env = make("rte_case14_realistic", test=True)
runner_params = env.get_params_for_runner()
runner = Runner(**runner_params, agentClass=DoNothingAgent)
res = runner.run(path_save=logs_path,
                 nb_episode=nb_episode, nb_process=4,
                 max_iter=-1, pbar=True)

Multi process running fails with the following:

python3.6/site-packages/grid2op/Runner/Runner.py", line 814, in run_parrallel
    [(self, pn, i, path_save) for i, pn in enumerate(process_ids)])
  File "/usr/lib/python3.6/multiprocessing/pool.py", line 274, in starmap
    return self._map_async(func, iterable, starmapstar, chunksize).get()
  File "/usr/lib/python3.6/multiprocessing/pool.py", line 644, in get
    raise self._value
  File "/usr/lib/python3.6/multiprocessing/pool.py", line 424, in _handle_tasks
    put(task)
  File "/usr/lib/python3.6/multiprocessing/connection.py", line 206, in send
    self._send_bytes(_ForkingPickler.dumps(obj))
  File "/usr/lib/python3.6/multiprocessing/reduction.py", line 51, in dumps
    cls(buf, protocol).dump(obj)
AttributeError: Can't pickle local object 'GridObjects.init_grid.<locals>.res'

[BDonnot]

Fixed in version v0.8.1