PLT-3562 Switch websocket over to post-connect authentication (#4327)

* Switch websocket over to post-connect authentication

* Add ability to specify token in websocket js driver, add unit tests

* Temporarily disable client websocket tests until issues are resolved

* Minor refactoring and fix status test

* Add isAuthenticated method to WebConn and minor status updates

model/websocket_message.go

@@ -26,6 +26,7 @@ const (
 	WEBSOCKET_EVENT_STATUS_CHANGE      = "status_change"
 	WEBSOCKET_EVENT_HELLO              = "hello"
 	WEBSOCKET_EVENT_WEBRTC             = "webrtc"
+	WEBSOCKET_AUTHENTICATION_CHALLENGE = "authentication_challenge"
 )
 
 type WebSocketMessage interface {