update docbook grammar, removing dnssec-looksaide

- this required modification to the code that generates grammar text for
  the documentation, because the "dnssec-lookaside" option spanned more
  than one line in doc/misc/options, so grepping out only the lines
  marked "// obsolete" didn't remove the whole option.  this commit adds
  an option to cfg_test to print named.conf clauses only if they don't
  have the obsolete, ancient, test-only, or not-yet-implemented flags
  set.

lib/isccfg/include/isccfg/cfg.h

@@ -485,6 +485,10 @@ cfg_printx(const cfg_obj_t *obj, unsigned int flags,
 
 #define CFG_PRINTER_XKEY        0x1     /* '?' out shared keys. */
 #define CFG_PRINTER_ONELINE     0x2     /* print config as a single line */
+#define CFG_PRINTER_ACTIVEONLY	0x4	/* print only active configuration
+					   options, omitting ancient,
+					   obsolete, nonimplemented,
+					   and test-only options. */
 
 /*%<
  * Print the configuration object 'obj' by repeatedly calling the
@@ -496,7 +500,7 @@ cfg_printx(const cfg_obj_t *obj, unsigned int flags,
  */
 
 void
-cfg_print_grammar(const cfg_type_t *type,
+cfg_print_grammar(const cfg_type_t *type, unsigned int flags,
 	  void (*f)(void *closure, const char *text, int textlen),
 	  void *closure);
 /*%<

lib/isccfg/include/isccfg/grammar.h

@@ -550,7 +550,7 @@ cfg_clause_validforzone(const char *name, unsigned int ztype);
  */
 
 void
-cfg_print_zonegrammar(const unsigned int zonetype,
+cfg_print_zonegrammar(const unsigned int zonetype, unsigned int flags,
 		      void (*f)(void *closure, const char *text, int textlen),
 		      void *closure);
 /*%<