help2man: generate man pages for genltl and ltlfilt

* tools/help2man, tools/x-to-1.in: New files, copied from gnulib
1af55d85d9762a679b4302d5995f05ccd883e956.
* configure.ac: Create x-to-1 and export CROSS_COMPILING.
* Makefile.am: Distribute help2man.
* src/bin/Makefile.am (SUBDIRS): New.
* src/bin/man/Makefile.am: New file.
* src/bin/man/genltl.x, src/bin/man/ltlfilt.x: New files.
* src/bin/genltl.cc: Document the RANGE in the options,
and move the bibliography to genltl.x.
* README: Document src/bin/man

src/bin/man/Makefile.am

@@ -0,0 +1,37 @@
+## -*- coding: utf-8 -*-
+## Copyright (C) 2012 Laboratoire de Recherche et Développement
+## de l'Epita (LRDE).
+##
+## This file is part of Spot, a model checking library.
+##
+## Spot is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 2 of the License, or
+## (at your option) any later version.
+##
+## Spot is distributed in the hope that it will be useful, but WITHOUT
+## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+## or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+## License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Spot; see the file COPYING.  If not, write to the Free
+## Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+## 02111-1307, USA.
+
+common_dep = $(top_builddir)/configure.ac
+x_to_1 = $(top_builddir)/tools/x-to-1
+convman = ARGP_HELP_FMT=header-col=0 $(SHELL) "$(x_to_1)" \
+          "$(PERL)" "$(top_srcdir)/tools/help2man -N"
+
+dist_man1_MANS = ltlfilt.1 genltl.1
+MAINTAINERCLEANFILES = $(dist_man1_MANS)
+man_aux = $(dist_man1_MANS:.1=.x)
+
+ltlfilt.1: $(common_dep) $(srcdir)/ltlfilt.x $(srcdir)/../ltlfilt.cc
+	$(convman) ../ltlfilt$(EXEEXT) $(srcdir)/ltlfilt.x $@
+
+genltl.1: $(common_dep) $(srcdir)/genltl.x $(srcdir)/../genltl.cc
+	$(convman) ../genltl$(EXEEXT) $(srcdir)/genltl.x $@
+
+