* README.gpgconf: Revert last change. Add new flags "default",
"default desc" and "no arg desc". Add new field ARGDEF. Add new
field FLAG to backend interface.
* gpgconf-comp.c (struct gc_option): Make flags of type unsigned
long.
(gc_component_list_options): Adjust type for flags.
Add default argument field.
(retrieve_options_from_program): Use "1" as value for non-option
arguments, not "Y".
(gc_component_change_options): Read in flags from input.
* gpgconf-comp.c (hextobyte): New function.
(percent_deescape): New function.
(get_config_pathname): Percent deescape pathname if taken from
option (default) value. Use default value only if it exists and
is not empty. Use empty string otherwise. Don't include leading
quote in pathname.
(change_options_program): Percent deescape string before writing
it out.