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/shebang-command/readme.md

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+# shebang-command [![Build Status](https://travis-ci.org/kevva/shebang-command.svg?branch=master)](https://travis-ci.org/kevva/shebang-command)
+
+> Get the command from a shebang
+
+
+## Install
+
+```
+$ npm install shebang-command
+```
+
+
+## Usage
+
+```js
+const shebangCommand = require('shebang-command');
+
+shebangCommand('#!/usr/bin/env node');
+//=> 'node'
+
+shebangCommand('#!/bin/bash');
+//=> 'bash'
+```
+
+
+## API
+
+### shebangCommand(string)
+
+#### string
+
+Type: `string`
+
+String containing a shebang.