Get increase and decrease of list indentation to work with complex cases.

Get increase and decrease of list indentation to work with complex cases.

* lisp/muse-colors.el: Miscellaneous whitespace fixes.
  (muse-colors-explicit-link): Minor logic tweak.  The indentation seems
  to indicate this interpretation, though parens are different.

* lisp/muse-mode.el: Miscellaneous whitespace fixes.
  (muse-alter-list-item-indentation): New function that alters the list
  structure at point.  The behavior to use is specified by the OPERATION
  argument.  Currently-supported operations are 'increase and 'decrease
  indentation level.  This now uses the same sort of list detection
  algorithm that is used during publishing, so it should work as expected
  for complicated cases.
  (muse-increase-list-item-indentation)
  (muse-decrease-list-item-indentation): Use
  `muse-alter-list-item-indentation'.
git-archimport-id: mwolson@gnu.org--2006/muse--main--1.0--patch-47