update readme

README.md

@@ -37,7 +37,7 @@ CDN
 <script type="text/javascript" src="https://cdn.pubnub.com/sdk/javascript/pubnub.4.20.1.js"></script>
 <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/fetch/0.11.1/fetch.js"></script>
 <script type="text/javascript" src="https://cdn.rawgit.com/ringcentral/ringcentral-js/3.2.2/build/ringcentral.js"></script>
-<script src="https://unpkg.com/[email protected]/build/index.js"></script>
+<script type="text/javascript" src="https://unpkg.com/[email protected]/build/index.js"></script>
 ```
 
 ## Usage
@@ -274,8 +274,9 @@ rcCallControl.refreshDevices().then(() => {
 
 ## TODO
 
-[x] Demo
-[x] Docs
-[ ] Account Level
-[ ] Conference Support
-[ ] Tests
+- [x] Extension Level
+- [x] Demo
+- [x] Docs
+- [ ] Account Level
+- [ ] Conference Support
+- [ ] Tests