Log Message:
Update docbook-xsl to 1.60.1.

Changes since 1.59.2:

Lots of bug fixes:
* Attributes to control the templates are now namespace qualified.
* Support use of titleabbrev in running headers and footers.
* Added (experimental) xref.with.number.and.title
  parameter to enable number/title cross references even when the
  default would be just the number.
* Generate part ToCs if they're requested.
* Use proportional-column-width() in header/footer tables.
* Handle alignment correctly when screenshot wraps a graphic in a figure.
* Format chapter and appendix cross references consistently.
* Attempt to support tables with multiple tgroups in FO.
* Output fo:table-columns in simplelist tables.
* Use titlepage.templates.xml for indexdiv and glossdiv formatting.
* Improve support for new bibliography elements.
* Added footnote.number.format, table.footnote.number.format,
  footnote.number.symbols, and table.footnote.number.symbols for better
  control of footnote markers.
* Added glossentry.show.acronyms.
* Suppress the draft-mode page masters when draft-mode is no.
* Make blank pages verso not recto. D'Oh!
* Improved formatting of ulink footnotes.
* Fixed bugs in graphic width/height calculations.
* Added class attributes to inline elements.
* Don't add .html to the filenames identified with the dbhtml PI.
* Don't force a ToC when sections contain refentrys.
* Make section title sizes a function of the body.master.size.