add websocket section in doc
add websocket section in doc

ashleysommer/sanic,lixxu/sanic,yunstanford/sanic,channelcat/sanic,channelcat/sanic,lixxu/sanic,yunstanford/sanic,lixxu/sanic,channelcat/sanic,yunstanford/sanic,ashleysommer/sanic,yunstanford/sanic,lixxu/sanic,ashleysommer/sanic,channelcat/sanic