Python client upload() bug

[unixpickle]

For the /v1/upload API, the request must have a training_dir key. However, the python client erroneously uses a key called directory instead:

data = {'directory': directory,
        'force': force,
        'resume': resume,
        'video_callable': video_callable}
self._post_request(route, data)

The upload() method was probably just never tested before.

Fixing this might save someone a bit of debugging time if they use the Python client as a guide for their own client.

[unixpickle]

My bad, I was looking at monitor_start in the client.