Merged from hodique@lifl.fr--2005 (patch 2-6), without the WikiWord change.

Merged from hodique@lifl.fr--2005 (patch 2-6), without the WikiWord change.

(Summary of changes that Yann made)

* muse-colors.el (muse-colors-link): Whitespace cleanup.

* muse-mode.el (muse-generate-index): Move index generation code into
  `muse-index-as-string'.
  (muse-index-as-string): New function that generates an index and
  returns it as a string, instead of placing it in a buffer like
  `muse-generate-index' used to.

Patches applied:

 * hodique@lifl.fr--2005/muse--yh--1.0--patch-2
   merge from mwolson@gnu.org--2005

 * hodique@lifl.fr--2005/muse--yh--1.0--patch-3
   Accept WikiWords as links [mostly rescinded]

 * hodique@lifl.fr--2005/muse--yh--1.0--patch-4
   merge from mwolson@gnu.org--2005/muse--main--1.0

 * hodique@lifl.fr--2005/muse--yh--1.0--patch-5
   Merged from mwolson@gnu.org--2005 (patch 60-62)

 * hodique@lifl.fr--2005/muse--yh--1.0--patch-6
   provide a string view of the index
git-archimport-id: mwolson@gnu.org--2005/muse--main--1.0--patch-63