code: function setFilename($el, $filenameTag, options) {
          var filenames = $.map($el[0].files, function (file) {return file.name}).join(', ');
  
          if (filenames === "") {
              filenames = options.fileDefaultHtml;
          } else {
              filenames = filenames.split(/[\/\\]+/);
              filenames = filenames[(filenames.length - 1)];
          }
  
          $filenameTag.text(filenames);
      }
docs: Updates the filename tag based on the value of the real input
  element.
  
  @param {jQuery} $el Actual form element
  @param {jQuery} $filenameTag Span/div to update
  @param {Object} options Uniform options for this element