code: def button(value = nil, options = {})
        options[:button] ||= {}
  
        options[:container] ||= {}
        options[:container][:class] = arrayorize(options[:container][:class]) << ::Formula.block_class
  
  
        @template.content_tag(::Formula.block_tag, options[:container]) do
          submit value, options[:button]
        end
      end
docs: Generate a form button.
  
   Options:
  
   * :container - add custom options to the container
   * :button    - add custom options to the button
  
   Usage:
  
     f.button(:name)
  
   Equivalent:
  
     <div class="block">
       <%= f.submit("Save")
     </div>