Improve customize interface for `muse-project-alist' once more.

Improve customize interface for `muse-project-alist' once more.

* lisp/muse-project.el (muse-project-alist-get): Allow cdr of each
  setting to be anything, since we now support settings that use lists.
  (muse-project): Vastly improve this by naming each setting and showing
  what exact type is required.  Handle case where a function is not
  defined yet.  Use a set for styles, which looks nice.  This is about as
  good as it can be ... unless we add some sort of inline documentation
  later on.  A setting was added for Yann's :force-publish tag.

* lisp/muse.el (muse-eval-lisp): Fix compile warning by not displaying
  project name.
git-archimport-id: mwolson@gnu.org--2005/muse--main--1.0--patch-139