Minor fixups for Vala support. * automake.in: $(VALAFLAGS) comes after $(AM_VALAFLAGS). * doc/automake.texi (Vala Support): Add some references, document AM_VALAFLAGS, streamline a bit. * lib/am/vala.am: Copyright blurb. * m4/vala.m4 (AM_PROG_VALAC): Rewrite using AS_VERSION_COMPARE. * tests/vala.test: Fix minor nits. * tests/vala1.test: Likewise. * tests/vala2.test: Likewise. * tests/vala3.test: Likewise. * tests/vala4.test: New test, for version argument of AM_PROG_VALAC. * tests/Makefile.am: Update. Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>