Update ruby-builder to 3.2.3.

3.1.2

* Removed css builder

3.1.3

* suppress warning while undefining object_id

3.1.4

* explicit blank content will not generate a self-closing tag

3.2.0

* Check if method was already cached before method definition.
* Change to String, raise_error last argument accept String
* Add test
* Cleanup of code
* Make changes to add option
* Update lib/builder/xmlbase.rb
* Cleaned up test case.
* Cleaned up explicit nil code a wee bit.
* Remove extraneous white spaces.
* Convert readme from rdoc to markdown.
* Tweek readme.
* Add us-ascii encoding declaration.
* Use old style hash literals for 1.8.x compatibility.
* Add # encoding: iso-8859-1 comment
* Add single quote attribute option.
* Update changes.
* More rdoc fixes.

(taca)