class ActiveAdmin::HasManyBuilder

def render_has_many_form(form_builder, parent, &block)

Renders the Formtastic inputs then appends ActiveAdmin delete and sort actions. 
def render_has_many_form(form_builder, parent, &block)
  index = parent && form_builder.send(:parent_child_index, parent)
  template.concat template.capture { yield(form_builder, index) }
  template.concat has_many_actions(form_builder, "".html_safe)
end