increase-ws-performance.md

How to increase WebSocket performance

There are 2 optional modules that provide a performance boost.

• npm install --save-optional bufferutil: efficiently performs operations (masking, unmasking) on the data payload
• npm install --save-optional utf-8-validate efficiently check if a message contains valid UTF-8

References:

• https://github.com/websockets/ws#opt-in-for-performance