Fix GNS3VM settings are lost at startup

Fix #926

gns3server/web/web_server.py

@@ -249,13 +249,6 @@ class WebServer:
                 time.sleep(1)  # this is to prevent too many request to slow down the server
         log.debug("UDP server discovery stopped")
 
-    @asyncio.coroutine
-    def _on_startup(self, *args):
-        """
-        Called when the HTTP server start
-        """
-        yield from Controller.instance().start()
-
     def run(self):
         """
         Starts the server.
@@ -295,9 +288,8 @@ class WebServer:
         for key, val in os.environ.items():
             log.debug("ENV %s=%s", key, val)
 
+        self._loop.run_until_complete(Controller.instance().start())
         self._app = aiohttp.web.Application()
-        # Background task started with the server
-        self._app.on_startup.append(self._on_startup)
 
         # Allow CORS for this domains
         cors = aiohttp_cors.setup(self._app, defaults={