x1092 Fallback to default location if it was not received from external service

If end-user uses adblock or other extension and access to ip-api.com is blocked
map will apper gray it will not be possible to do anything with it.
If that happens we need to set default location and zoom out for better view.

flask_admin/static/admin/js/form.js

@@ -151,6 +151,8 @@
           // look up user's location by IP address
           $.getJSON("http://ip-api.com/json/?callback=?", function(data) {
             map.setView([data["lat"], data["lon"]], 12);
+          }).fail(function() {
+              map.setView([0, 0], 1)
           });
         }