maint: update copyright notices to include 2014.

* .x-update-copyright: New file. Exclude files not owned by this
project from update-copyright rules.
* build-aux/.gitignore: Add update-copyright.
* bootstrap.conf, configure.ac, local.mk: Bump copyright year.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
slingshot: sync with upstream.

Fix the annoying contest.sed file dropping bug.
* slingshot: Sync with upstream.
* bootstrap: Sync with slingshot.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>