automake, aclocal: update copyright year in output Fixes automake bug#11356. * aclocal.in, automake.in: Add copyright year '2012' in the version message. Ditto for the copyright notice in the generated Makefile.in or aclocal.m4 files; and for those, since we are at it, prefer using a range for copyright years, rather than listing each copyright year individually. Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>