add large screenshot and use title case
add large screenshot and use title case

Lightstreamer/Lightstreamer-example-RoomBall-client-javascript,Weswit/Lightstreamer-example-RoomBall-client-javascript,Weswit/Lightstreamer-example-RoomBall-client-javascript,Lightstreamer/Lightstreamer-example-RoomBall-client-javascript