Now, each unofficial build has a version "number" like 2.61a-19-58dd,
which indicates that it is built using the 19th change set
(in _some_ repository) following the "v2.61a" tag, and that 58dd
is a prefix of the commit SHA1.
* build-aux/git-version-gen: New file.
* configure.ac: Run it to set the version.
(AM_INIT_AUTOMAKE): Don't check NEWS here.
* Makefile.am (dist-hook): Arrange so that .version appears only
in distribution tarballs, never in a checked-out repository.
* .gitignore: Add .version here, too. Just in case.
* tests/Makefile.am ($(srcdir)/package.m4): Depend on Makefile,
not configure.ac, now that the version number changes automatically.
Ensure that $(VERSION) is up to date for dist-related targets.
* GNUmakefile: Arrange to rerun autoconf, if the version reported by
git-version-gen doesn't match $(VERSION), but only for dist targets.
* aclocal.m4: Remove.
* configure: Remove.
* Makefile.in: Remove, along with all other Makefile.in in subdirs.
* .gitignore: Add aclocal.m4, configure and Makefile.in. Sort.
* README-hacking: New file: how to build from just-checked-out sources.
