A backport of scheme-mode from GNU Emacs 29+

Paul Eggert 6a54bcf4d4 Merge from emacs-24; up to 2012-12-06T01:39:03Z!monnier@iro.umontreal.ca пре 12 година
COPYING f42a75b8d8 Restore files that I seem to have mistakenly deleted. пре 14 година
scheme.el ece6eca08a Merge from emacs-24; up to 2012-12-06T01:39:03Z!monnier@iro.umontreal.ca пре 12 година