release: create new release branch at v1 tag.

* build-aux/release.mk (check-in-release-branch): If there is no
release branch yet, create the new at the v1 tag rather than the
current HEAD of master (which is probably a post-release admin-
istrivia commit).

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
release: ensure git rockspec is available for announcement.

* build-aux/release.mk (announcement): Add depedency on scm_rockspec.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
release: add .PHONY tag to push and mail targets.

* build-aux/release.mk (push, mail): Move to end of file. Add
.PHONY tag.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
release: add maintainer support scripts to distribution by default.

* build-aux/release.mk (release_extra_dist): List all the support
scripts used by release.mk.
(EXTRA_DIST): Append them.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
sanity: port over gnulib sanity checking rules.

* build-aux/sanity.mk: Sanity checks from gnulib maint.mk.
* README.md: Document it.
* GNUmakefile: Include it.
(distcheck): Run sanity checks too.
(ME): Fix typo found by sanity checks.
* build-aux/release.mk: Fix whitespace errors found by sanity
checks.
* build-aux/rockspecs.mk: Fix typo found by sanity checks.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
release: add submodule checks to release rules.

* build-aux/release.mk (no-submodule-changes): Make sure we can't
accidentally release with unchecked-in submodule changes.
(public-submodule-commit): Make sure we can't accidentally release
with unpushed local submodule changes.
(submodule-checks): List them.
(release): Run the checks.

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

* NEWS: updated.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
Release version 2

* NEWS: Record release date.
maint: post-release administrivia.

* NEWS: Add header line for next release.
* .prev-version: Record previous version.
* ./Makefile.am (old_NEWS_hash): Auto-update.

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