v0.27.0 - Websocket support

In this release we include preliminary Websocket support; feedback is most welcome.

let echo (webSocket : WebSocket) =
  fun cx -> async{
    let loop = ref true
    while !loop do
      let! msg = webSocket.read()
      match msg with
      | (Text, data, true) ->
        let str = UTF8.toString data
        do! webSocket.send Text data true
      | (Ping, _, _) ->
        do! webSocket.send Pong [||] true
      | (Close, _, _) ->
        loop := false
      | _ -> ()
    return! Control.CLOSE cx
  }

let app : WebPart =
  choose [
    path "/websocket" >>= handShake echo
    GET >>= choose [ path "/" >>= file "index.html"; browseHome ];
    NOT_FOUND "Found no handlers."
    ]

We also fixed a bug in the Razor module d295582