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-regex/readme.md

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+# shebang-regex [![Build Status](https://travis-ci.org/sindresorhus/shebang-regex.svg?branch=master)](https://travis-ci.org/sindresorhus/shebang-regex)
+
+> Regular expression for matching a [shebang](https://en.wikipedia.org/wiki/Shebang_(Unix)) line
+
+
+## Install
+
+```
+$ npm install shebang-regex
+```
+
+
+## Usage
+
+```js
+const shebangRegex = require('shebang-regex');
+
+const string = '#!/usr/bin/env node\nconsole.log("unicorns");';
+
+shebangRegex.test(string);
+//=> true
+
+shebangRegex.exec(string)[0];
+//=> '#!/usr/bin/env node'
+
+shebangRegex.exec(string)[1];
+//=> '/usr/bin/env node'
+```
+
+
+## License
+
+MIT © [Sindre Sorhus](https://sindresorhus.com)