* configure.ac: Use AC_CONFIG_AUX_DIR. Remove args from
AM_INIT_AUTOMAKE. Replace AM_CONFIG_HEADER by AC_CONFIG_HEADER.
* compile, config.guess, config.sub, depcomp, install-sh, ltmain.sh
* mkinstalldirs, texinfo.texi: Move to build-aux/ and update from
gnulib (c042abf).
* build-aux/mdate-sh, build-aux/missing: Install via automake -a -c.
Update autogen.sh for changed config dir.
* autogen.sh: Adjust for scripts dir change. Update W32 toolprefix
list.
* build-aux/gitlog-to-changelog: New script. Taken from gnulib.
* build-aux/git-log-fix: New file.
* build-aux/git-log-footer: New file.
* build-aux/git-hook/commit-msg: New script.
* doc/HACKING: New file.
* ChangeLog: New file.
* Makefile.am (EXTRA_DIST): Add new files.
(gen-ChangeLog): New.
(dist-hook): Run gen-ChangeLog.
* autogen.sh: Install commit-msg hook for git.
Rename all ChangeLog files to ChangeLog-2011.