div and span is inter-changable as they can be styled via css, But we should
really use div element within fieldset instead of span element by default. I
believe using div here is the sane default. ;-)
below urls are for references:
http://www.learnwebdesignonline.com/htmlcourse/span-div.htm
http://archive.thedevweb.com/2007/0502.html
=for layout field
-<span class="field_container_field">
+<div class="field_container_field">
[% call_next %]
-</span>
+</div>
=cut
=for layout widget
-<span class="[% field_class %]">[% label_fragment %] [% field %] [% message_fragment %]</span>
+<div class="[% field_class %]">[% label_fragment %] [% field %] [% message_fragment %]</div>
=for layout label