Rewrite the ltl2tgba bench using ltlcross

* bench/ltl2tgba/sum.py: New file.
* bench/ltl2tgba/.gitignore, bench/ltl2tgba/Makefile.am,
bench/ltl2tgba/README, bench/ltl2tgba/algorithms, bench/ltl2tgba/big,
bench/ltl2tgba/defs.in, bench/ltl2tgba/known, bench/ltl2tgba/small:
Rewrite this benchmark completely.  Also drop support of Wring and
Modella, as we cannot get them to work reliably.
* bench/ltl2tgba/formulae.ltl: Rewrite in Spot's syntax.
* bench/ltl2tgba/lbtt2csv.pl, bench/ltl2tgba/ltl2baw.in,
bench/ltl2tgba/parseout.pl: Delete these scripts, no
longer needed.
* configure.ac: Do not output ltl2baw.pl anymore.

bench/ltl2tgba/small

@@ -1,10 +1,7 @@
 #!/bin/sh
 # -*- shell-script -*-
-# Copyright (C) 2011 Laboratoire de Recherche et Developpement de
+# Copyright (C) 2012, 2013 Laboratoire de Recherche et Developpement de
 # l'Epita (LRDE)
-# Copyright (C) 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
-# département Systèmes Répartis Coopératifs (SRC), Université Pierre
-# et Marie Curie.
 #
 # This file is part of Spot, a model checking library.
 #
@@ -22,58 +19,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 . ./defs
-
-conffile=small.cfg
-logfile=small.log
-sumfile=small.txt
-
 . "$srcdir/algorithms"
 
-cat >>"$conffile" <<EOF
-GlobalOptions
-{
-   Rounds = 100
-   Interactive = Never
-#   Verbosity = 5
-#   ComparisonCheck = no
-   ConsistencyCheck = no
-#   IntersectionCheck = no
-   TranslatorTimeout = 15min
-}
-
-StateSpaceOptions
-{
-   Size = 200
-   Propositions = 4
-}
-
-FormulaOptions
-{
-  Size = 10
-  Propositions = 4
-
-  AbbreviatedOperators = No
-  GenerateMode = Normal
-  OutputMode = NNF
-  PropositionPriority = 50
-
-  TruePriority = 1
-  FalsePriority = 1
-
-  AndPriority = 10
-  OrPriority = 10
-  XorPriority = 0
-  EquivalencePriority = 0
-
-  BeforePriority = 0
-  StrongReleasePriority = 0
-  WeakUntilPriority = 0
-
-  UntilPriority = 30
-  DefaultOperatorPriority = 15
-}
-
-EOF
-
-"$LBTT" --configfile="$conffile" | tee "$logfile"
-"$srcdir"/parseout.pl "$logfile" | tee "$sumfile"
+$RANDLTL -n 100 --tree-size=10 p1 p2 p3 p4 | ltlfilt --nnf |
+$LTLCROSS "$@" --csv=small.csv --json=small.json 2>&1 | tee small.log