Find an alternative to websocket implementation

[nemesifier]

We should replace the initial prototype websocket implementation with a more mature solution.

I've been following a few projects:

• https://github.com/moccu/django-omnibus
• https://github.com/jrief/django-websocket-redis
• https://github.com/jonashagstedt/swampdragon

We need a solution that allows us to do mainly 3 things:

• send notifications
• update the UI when data changes
• streamline loading huge data, eg: instead of loading 40.000 nodes in one HTTP request, we could send 500/1000 nodes with several websocket server sent requests.

The solution that looks more suited for the job is Swampdragon. websocket-redis seems purposely limited and simplified.

At this stage it would be enough to do the following:

• include swampdragon in nodeshot
• find a way to send notifications to logged in users
• update the notification UI when notifications are received
• set good defaults for swampdragon in nodeshot.conf.settingsso that swampdragon can work out of the box in development and production
• add instructions to the development and production install on how to run the websocket server