def join(array, separator)
      first = true
      array.each do |item|
        if !first
          if separator.is_a? Widget
            widget separator
          else
            text separator
          end
        end
        first = false
        if item.is_a? Widget
          widget item
        else
          text item
        end
      end
    end
def join(array, separator)
      first = true
      array.each do |item|
        if !first
          if separator.is_a? Widget
            widget separator
          else
            text separator
          end
        end
        first = false
        if item.is_a? Widget
          widget item
        else
          text item
        end
      end
    end
Render (like to_html) but stripping all tags and inserting some
 appropriate formatting. Currently we format p, br, ol, ul, and li
 tags.
 Emits the result of joining the elements in array with the separator.
 The array elements and separator can be Erector::Widget objects,
 which are rendered, or strings, which are html-escaped and output.