Fix typo in grammar.

Add lexertl.

src/test.cpp

@@ -4,6 +4,15 @@
  * Licensed under the GNU GPL v2.
  */
 
+// this file is auto generated from grammar/grammar.y
+// but it does not work yet
+// #include "grammar.h"
+
+#include "lexertl/generator.hpp"
+#include "lexertl/lookup.hpp"
+#include "lexertl/rules.hpp"
+#include "lexertl/state_machine.hpp"
+
 int main() {
     return 0;
 }