FRE-600: Fix code review blockers

- Consolidated duplicate UndoManagers to single instance
- Fixed connection promise to only resolve on 'connected' status
- Fixed WebSocketProvider import (WebsocketProvider)
- Added proper doc.destroy() cleanup
- Renamed isPresenceInitialized property to avoid conflict

Co-Authored-By: Paperclip <noreply@paperclip.ing>

node_modules/fastq/example.js

@@ -0,0 +1,14 @@
+'use strict'
+
+/* eslint-disable no-var */
+
+var queue = require('./')(worker, 1)
+
+queue.push(42, function (err, result) {
+  if (err) { throw err }
+  console.log('the result is', result)
+})
+
+function worker (arg, cb) {
+  cb(null, 42 * 2)
+}