(prot_a_type.__init__): Initialize __recommended to 0.
(prot_a_type.use): New argument: recommended.  All callers
	updated.  Set the __recommended flag once a recommended
	request or async uses this type.
(prot_a_builtin.use_recurse): Ditto.
(prot_a_type.recommended): New method.
(lexer.__parse_type): Replaced the protover arguemnt with a
	request object.  All callers updated.
(lexer.__parse_request_arg): Ditto.
(generate_stable_output): New argument: filename,
	only_recommended.
(generate_summary_output): New function.