TT#107700 fix README: is_private is bool

Author: spartanz51 <spartanz51@live.fr>
Pull request: https://github.com/sipwise/janus-client/pull/24/

Change-Id: I9e4511a60b7e3e993453d2fd3c4b6c8a9d46abb5

README.md

@@ -104,7 +104,7 @@ client.createSession().then((session)=>{
 ```javascript
 videoRoomHandle.create({
    publishers: 3,
-   is_private: 'no',
+   is_private: false,
    secret: '****',
    pin: '****',
    audiocodec: 'opus',