[Fix #508]Api GeoJson: export cadastre

app/serializers/cadastre_serializer.rb

@@ -0,0 +1,17 @@
+class CadastreSerializer < ActiveModel::Serializer
+  attributes :value, :type_de_champ
+
+  def value
+    object.geometry
+  end
+
+  def type_de_champ
+    {
+      id: -1,
+      libelle: 'cadastre',
+      type_champ: 'cadastre',
+      order_place: -1,
+      descripton: ''
+    }
+  end
+end