muse-xml: Separate section from title.
* experimental/muse-xml.el (muse-xml-markup-strings): Add "level"
attribute to sections. Use separate <title> tag to handle the title of
a section. Thanks to drkm for the suggestion.
* lisp/muse-mode.el (muse-mode): Code indentation, no func change.
* lisp/muse-publish.el (muse-publish-markup-heading)
(muse-publish-section-close): Pass level to markup strings for all
section-related tags.
* lisp/muse.el (muse-page-name): Handle case where buffer-file-name is
not defined.
git-archimport-id: mwolson@gnu.org--2005/muse--main--1.0--patch-177