Attempt to make new syntaxes easier to support.

Attempt to make new syntaxes easier to support.

* lisp/muse-colors.el (muse-colors-explicit-link): Use `muse-get-link'
  and `muse-get-link-data'.

* lisp/muse-journal.el (muse-journal-rss-munge-buffer): Ditto.

* lisp/muse-mode.el (muse-edit-link-at-point): Ditto.
  (muse-make-link): Change argument name.

* lisp/muse.el (muse-handle-explicit-link): Ditto.
  (muse-get-link, muse-get-link-desc): New functions that return the link
  and the link description, respectively, from the given TARGET.  The
  idea is that at least one other markup syntax puts descriptions before
  links, so all they would have to do is re-define these two functions.
git-archimport-id: mwolson@gnu.org--2006/muse--main--1.0--patch-65