remove origin check of websocket (for now)

https://stackoverflow.com/questions/24851207/tornado-403-get-warning-when-opening-websocket/25071488#25071488

app/cesium_web_server.py

@@ -40,6 +40,9 @@ def post(self):
 class DefaultWebSocket(tornado.websocket.WebSocketHandler):
     def initialize(self, callback):
         self.callback = callback
+
+    def check_origin(self, origin):
+        return True
 
     def open(self):
         if APP_DEBUG: