Websocket Support (#937)

* Atom / RSS meta link

* Spike

* Feeling good about this spike now

* Remove document.collection

* Remove koa.ctx from all presenters to make them portable outside requests

* Remove full serialized model from events
Move events.add to controllers for now, will eventually be in commands

* collections.create event
parentDocument -> parentDocumentId

* Fix up deprecated tests

* Fixed: Doc creation

* documents.move

* Handle collection deleted

* 💚

* Authorize room join requests

* Move starred data structure
Account for documents with no context on sockets

* Add socket.io-redis

* Add WEBSOCKETS_ENABLED env variable to disable websockets entirely for self hosted
New installations will default to true, existing installations to false

* 💚 No need for promise response here

* Reload notice

server/presenters/integration.js

@@ -1,7 +1,7 @@
 // @flow
 import { Integration } from '../models';
 
-function present(ctx: Object, integration: Integration) {
+export default function present(integration: Integration) {
   return {
     id: integration.id,
     type: integration.type,
@@ -16,5 +16,3 @@ function present(ctx: Object, integration: Integration) {
     updatedAt: integration.updatedAt,
   };
 }
-
-export default present;