add amenity=shelter to Overpass layers (#433)

layers/config/tree.js

@@ -172,6 +172,7 @@ BR.confLayers.tree = {
             'picnic_site',
             'viewpoint',
             'wilderness_hut',
+            'shelter',
         ]
     }
 };

layers/overpass/tourism/shelter.geojson

@@ -0,0 +1,12 @@
+{
+  "geometry": null,
+  "properties": {
+    "name": "Shelter",
+    "id": "shelter",
+    "overlay": true,
+    "dataSource": "OverpassAPI",
+    "icon": "temaki-picnic_shelter",
+    "query": "nwr[amenity=shelter];"
+  },
+  "type": "Feature"
+}

package.json

@@ -345,7 +345,8 @@
                 "icons/bunk_beds.svg",
                 "icons/museum.svg",
                 "icons/spotting_scope.svg",
-                "icons/cabin.svg"
+                "icons/cabin.svg",
+                "icons/picnic_shelter.svg"
             ]
         },
         "@fortawesome/fontawesome-free": {