Publish captions for images that have descriptions.

Publish captions for images that have descriptions.

* lisp/muse-colors.el (muse-colors-lisp-tag): Use a simpler regexp to
  match the tags.
  (muse-colors-explicit-link): Show images in link descriptions if
  inlined images are enabled.

* lisp/muse-docbook.el (muse-docbook-markup-strings): Add definitions for
  'image-with-desc, 'image, and 'image-link.
  (muse-docbook-markup-paragraph): If an inlined image begins a
  paragraph, insert <para> before it.
  (muse-docbook-fixup-images): New function that upper-cases the "format"
  attribute of the <imagedata> tag.
  (muse-docbook-finalize-buffer): Call it.

* lisp/muse-html.el (muse-html-markup-strings): Publish images with
  descriptions as centered tables, with a centered caption underneath.
  The resulting look is consistent with the way that they are published
  in the LaTeX style.  Thanks to Jody Klymak for the suggestion.
  (muse-xhtml-markup-strings): Ditto, but XHTML apparently has no valid
  way to center a table.
  (muse-html-markup-paragraph): Use class="image" instead of "image-link"
  for paragraphs that start with an embedded image.

* lisp/muse-latex.el (muse-latex-fixup-dquotes): Go to beginning of
  document, instead of relying on caller to do this for us.

* lisp/muse-publish.el (muse-publish-url): Use 'image instead of
  'image-link and 'image-link in place of 'url-with-image.  Separate the
  image file from its extension so that docbook and texinfo can publish
  images correctly.
  (muse-publish-markup-link): Don't force a description if one is not
  given.  This fixes a bug where images without descriptions were being
  published as 'image-with-desc instead of 'image.

* lisp/muse-texinfo.el (muse-texinfo-markup-strings): Improve image
  markup to achieve an effect similar to that of the LaTeX publishing
  style.  Simplify 'url string.

* lisp/muse.el (muse-replace-regexp-in-string): Save match data when we
  have to use the custom version of this function.

* muse.texi (Images): Explain how to toggle inlining of images and give
  better examples.  Mention captions and that captioned images should not
  be used inside of text paragraphs.
  (Markup Strings): Bring up-to-date with the changes made since 3.02.
git-archimport-id: mwolson@gnu.org--2006/muse--main--1.0--patch-177