add geo location center for config-mode-geo-location-osm

site.conf

@@ -43,6 +43,16 @@
     -- Show/hide the altitude field
     geo_location = {
       show_altitude = true,
+      -- for gluon-config-mode-geo-location-osm
+      osm = {
+        center = {
+          lat = 54.367758524,
+          lon = 9.343872070,
+        },
+        zoom = 11,
+        -- the default is https://cdn.rawgit.com/openlayers/openlayers.github.io/master/en/v5.2.0
+        -- openlayers_url = 'https://mirror in kiel?',
+      },
     },
     -- define if the contact field is obligatory (optional)
     -- disabled in 2017.1.8