An extension, which can be used with Base.build to add standard
module (header, body, footer) support to a Widget class.

3.1.1

* No changes.

3.1.0

* Changed widget stdmod renderUI/syncUI/bindUI to Y.before, so that they are 
  called before the Widget implementation, and setup the header/body/footer
  node references for the Widget impl to use.

* Setting section content to "" will now create the respective section. 

* Fixed fillHeight, to work with contentBox height, now that it fills boundingBox

* Fixed setStdModContent("markupString", AFTER | BEFORE) so that it uses 
  node.append, node.prepend instead of innerHTML to maintain listeners.

* fillHeight is now invoked when height is changed. Was not being invoked 
  because of a typo in the event name.

3.0.0

* Cleaned up the way headerContent, bodyContent, footerContent are configured,
  so that the actual stored value is always accurate, without the need for a 
  getter which talks to the DOM directly.

* Recreate sections from TEMPLATE string for each instance, instead of
  cloning a class level cached Node instance, so that ownerDocument
  can be set to match the content box.

* Replaced use of innerHTML for progressive enhancement use case with 
  document fragment when parsing and then setting headerContent, bodyContent,
  footerContent in HTML_PARSER impl, to maintain event listeners etc.

3.0.0 beta 1

No Changes

3.0.0PR2 - Initial release
