1.110   2011-03-10
  - Added change log in the distribution.
  - TextStyle: added 'variant' option.
  - Document: XML indent if debug mode, added register_style() as an alias
  for insert_style(); bug fix in get_style().
  - Element.pm: Bug fixes and improvements regarding XML imports.
  - Style.pm : Number style handling improvement.
  - All: many comment changes.
  - Doc updates.
1.111   2011-03-30
  - Table.pm: Added out of range security to get_rows() and get_cells();
  improved cell span handling.
  - Document.pm: Added the 'handlers' and 'roots' options with get_part().
  - TextElement.pm: Added reference mark support methods.
  - Detail change in t/test01_write.t
  - Doc improvements.