Add taxonomies controller from spree_backend

app/controllers/spree/admin/taxonomies_controller.rb

@@ -0,0 +1,21 @@
+module Spree
+  module Admin
+    class TaxonomiesController < ResourceController
+      respond_to :json, :only => [:get_children]
+
+      def get_children
+        @taxons = Taxon.find(params[:parent_id]).children
+      end
+
+      private
+
+      def location_after_save
+        if @taxonomy.created_at == @taxonomy.updated_at
+          edit_admin_taxonomy_url(@taxonomy)
+        else
+          admin_taxonomies_url
+        end
+      end
+    end
+  end
+end