Add Django integration

[hballard]

Looking into options. Channels, django-websocket-redis, or django-socketio...

For anybody that uses Django (I don't)...is channels now the preference for real-time?

[Thibaut-Fatus]

From my understanding channels are the way to go on the latest django versions. We've been using django-websocket-redis and it feels quite rought, even if it does the job.

[hballard]

Took me a couple more days...but I pushed the most recent commits on the executor refactoring for adding asyncio compatability (and then use this structure as a basis for implementing Django channels if possible).

Here #19.

I've still working on getting the last tests to pass for the transport server class for Asyncio, but should be finished by the weekend I think.