Better fix for new tornado version

cps/server.py

@@ -288,4 +288,5 @@ class WebServer(object):
             if _GEVENT:
                 self.wsgiserver.close()
             else:
-                self.wsgiserver.add_callback_from_signal(self.wsgiserver.stop)
+                self.wsgiserver.call_later(1.0, self.wsgiserver.stop)
+                # self.wsgiserver.add_callback()

cps/static/js/main.js

@@ -397,11 +397,6 @@ $(function() {
             success: function success() {
                 $("#spinner").show();
                 setTimeout(restartTimer, 3000);
-            },
-            error: function (xhr) {
-                // Fix for new tornado versions , not returning a response during restart
-                $("#spinner").show();
-                setTimeout(restartTimer, 3000);
             }
         });
     });