* .x-update-copyright: Add entry for bootstrap.
* bootstrap: Remove 2011 from copyright years. The bootstrap
version we're currently using comes from an older version of
gnulib.
* bootstrap.conf (bootstrap_sync): Add comments explaining this
issue.
(cherry picked from commit 355bdbdc72)
* gnulib: Update.
* .x-update-copyright (COPYING): Add as it's no longer implied
when .x-update-copyright is present.
* cfg.mk (update-copyright-local): Remove, now ignored.
(update-copyright): Declare update-b4-copyright as a dependency.
(cherry picked from commit c67e466f9d)