(gnulib_extra_files): Add build-aux/announce.gen. (slurp): Adjust .gitignore files like .cvsignore files. * build-aux/announce-gen: Remove from CVS, since bootstrap now creates this.
* configure.ac, Makefile.am: Use build-aux. * config/prev-version, config/announce-gen, config/Makefile.am: Move to... * build-aux/prev-version, build-aux/announce-gen, * build-aux/Makefile.am: here.