Represents a WebSocket connection

This GenServer will handle the whole lifecycle of one WebSocket connection.

Setup

{:ok, pid} = GenServer.start_link(Tube.Websocket,
  uri: "ws://localhost:4000/ws",
  opts: [parent: self])
:ok = Tube.Websocket.connect(pid)

This will open a WebSocket connection to ws://localhost:4000/ws.

Incoming frames will be sent via message passing to the pid given in opts.parent.

Messages to parent

• {:websocket, :frame, frame}
• {:websocket, :open}
• {:websocket, :closed}