add speedtest server

public/API/mainMenu.json

@@ -179,6 +179,11 @@
                 "name": "Passwort Generator",
                 "url": "/passwordgen.html",
                 "type": "link"
+            },
+            {
+                "name": "Speedtest Server",
+                "url": "//jonasled.speedtestcustom.com",
+                "type": "link"
             }
         ]
     },