Add a benchmark using Kristin Y. Rozier's LTLcounter scripts.

* bench/ltlcounter/README, bench/ltlcounter/run,
bench/ltlcounter/plot.gnu, bench/ltlcounter/defs.in,
bench/ltlcounter/Makefile.am: New files.
* bench/Makefile.am (SUBDIRS): Add ltlcounter.
* configure.ac (AC_CONFIG_FILES): Adjust.
* THANKS: Add her.

bench/ltlcounter/Makefile.am

@@ -0,0 +1,23 @@
+# Copyright (C) 2009 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.
+
+EXTRA_DIST = run plot.gnu
+
+CLEANFILES = results.fm results.lacim results.fm.eps results.lacim.eps