def td_bln(*args)
      options = canonicalize_options(args.extract_options!)
      options = ensure_class(options, 'c')
      
      content_tag(:td, bln(*args), options)
    end
def td_bln(*args)
      options = canonicalize_options(args.extract_options!)
      options = ensure_class(options, 'c')
      
      content_tag(:td, bln(*args), options)
    end
Same as +bln+ but wrapped in a TD and centered (w/rail_view_helper.css)

 @example
   td_bln(true)  #=> <td class="c">&#10004;</td>
 @return [String]