Adjusting ID and Title of Big Blue Button Meeting

We currently generate the ID of a Big Blue Button Meeting for Video Calls randomly. As suggested by @GhaziTriki we should generate them the following way:

- meeting Id: 
 * private chat: zulip-deployment-id-owner-id-user
 * stream topic: zulip-deployment-id-stream-id-topic-id
- meeting name:
 * private chat: User Name Room
 * stream topic: stream - topic

The problem I see in that is that using the formats for the id that would mean that there can not be different meetings in one stream/pm chat. I think a time aspect should be included. (like appending the unix timestamp)

[timabbott]

I feel like we could generate the IDs still randomly and just configure the name based on the current compose box location at the time the request is made to create them?

[aero31aero]

@strifel we can simply pass some JSON to the API call and write

data = json.loads(request.body.decode("utf-8"))
meeting_title = data['meeting_title']

in zerver/views/video_calls.py:164:def get_bigbluebutton_url