rework roles with rolify

db/migrate/20140711072651_add_description_and_resource_to_roles.rb

@@ -0,0 +1,10 @@
+class AddDescriptionAndResourceToRoles < ActiveRecord::Migration
+  def change
+    add_column :roles, :description, :string
+    add_reference :roles, :resource, polymorphic: true
+
+    add_index(:roles, :name)
+    add_index(:roles, [:name, :resource_type, :resource_id])
+    add_index(:roles_users, [:user_id, :role_id])
+  end
+end