Pandoc-fignos

* Use nonbreaking space between ref name and number in caption
(pandoc-xnos Issue 14).
* Require pandoc-xnos 2.5.0 (updated to work with pandoc 2.11;
pandoc-fignos Issue 85).

* Require pandoc-xnos 2.4.2 (bug fix release).

* Updated to work with pandoc 2.10.
* Fixed figure number reset problem for html, docx (Issue 76).

* Added html/epub subfigures support (Issue 50).

* Documented LaTeX subfigures support (Issue 50).

* Warns about duplicate reference targets.