Fix column in LTL error messages, it was off by one.

* src/ltlparse/fmterror.cc (format_parse_errors): Count columns
starting at 1.  Older Bison used to start at 0 but changed to
match the GNU Coding Standards.
* src/ltltest/parseerr.test: Add a test case.

src/ltltest/parseerr.test

@@ -1,5 +1,5 @@
 #! /bin/sh
-# Copyright (C) 2009 Laboratoire de Recherche et Développement
+# Copyright (C) 2009, 2010 Laboratoire de Recherche et Développement
 # de l'Epita (LRDE).
 # Copyright (C) 2003, 2004 Laboratoire d'Informatique de Paris 6 (LIP6),
 # département Systèmes Répartis Coopératifs (SRC), Université Pierre
@@ -30,7 +30,7 @@
 
 check()
 {
-  run 1 ../ltl2text "$1" >stdout
+  set +x; run 1 ../ltl2text "$1" >stdout 2>stderr; set -x
   if test -n "$2"; then
     echo "$2" >expect
   else
@@ -43,9 +43,21 @@ check()
     cat stdout
     echo "instead of"
     cat expect
-    rm -f stdout expect
     exit 1
   fi
+
+  if test -n "$3"; then
+    echo "$3" >expect
+    if cmp stderr expect; then
+      :
+    else
+      echo "==== Error output was ===="
+      cat stderr
+      echo "==== instead of ===="
+      cat expect
+      exit 1
+    fi
+  fi
 }
 
 # Empty or unparsable strings
@@ -72,3 +84,12 @@ run 0 ../equals -E 'a & (a + b' 'a & (a + b)'
 run 0 ../equals -E 'a & (a + b c' 'a & (0)'
 run 0 ../equals -E 'a & (+' 'a & (0)'
 run 0 ../equals -E 'a & ('  'a & (0)'
+
+check 'a - b' 'AP(a)' '>>> a - b
+      ^
+syntax error, unexpected $undefined
+
+>>> a - b
+      ^^^
+ignoring trailing garbage
+'