Add park layer

layers/park/park.yaml

@@ -0,0 +1,22 @@
+layer:
+  id: "park"
+  description: |
+      Landuse is used to describe use of land by humans.At lower zoom levels this is
+      from Natural Earth data for residential (urban) areas and at higher zoom levels mostly OSM `landuse` tags.
+  buffer_size: 4
+  fields:
+    class: |
+        More generalized groups of either `park`, `school`, `hospital`, `railway`,
+        `cemetery`, `military`, `residential`. Use this to assign general for landuse.
+    subclass: |
+        Original value of either the `amenity`, `landuse`, `leisure` or `boundary` tag.
+        Use this to do more precise styling.
+  datasource:
+    geometry_field: geometry
+    query: (SELECT geometry, class, subclass FROM layer_park(!bbox!, z(!scale_denominator!))) AS t
+schema:
+  - ./class.sql
+  - ./layer.sql
+datasources:
+  - type: imposm3
+    mapping_file: ./mapping.yaml