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/revision.js

@@ -2,15 +2,13 @@
 import { Revision } from '../models';
 import presentUser from './user';
 
-function present(ctx: Object, revision: Revision) {
+export default function present(revision: Revision) {
   return {
     id: revision.id,
     documentId: revision.documentId,
     title: revision.title,
     text: revision.text,
     createdAt: revision.createdAt,
-    createdBy: presentUser(ctx, revision.user),
+    createdBy: presentUser(revision.user),
   };
 }
-
-export default present;