Propagate more token_number_t.

* src/gram.h (token_number_as_item_number)
(item_number_as_token_number): New.
* src/output.c (GENERATE_OUTPUT_TABLE): New.
Use it to create output_item_number_table and
output_token_number_table.
* src/LR0.c, src/derives.c, src/gram.c, src/gram.h, src/lalr.c,
* src/lex.c, src/nullable.c, src/output.c, src/print.c,
* src/print_graph.c, src/reader.c, src/reduce.c, src/state.h,
* src/symtab.c, src/symtab.h: Use token_number_t instead of shorts.

src/symtab.h

@@ -43,15 +43,19 @@ typedef enum
 
 /* Internal token numbers. */
 typedef short token_number_t;
+
 #define SUNDEF  -1              /* For undefined user number. */
 #define SALIAS	-9991		/* for symbol generated with an alias */
 
+#define NUMBER_UNDEFINED ((token_number_t) -1)
+
 struct symbol_s
 {
   /* The key, name of the symbol. */
   char *tag;
   /* Its type. */
   char *type_name;
+
   token_number_t number;
   short prec;
   associativity assoc;