* keylist.c (list_cert_colon): New arg HAVE_SECRET, print "crs"
when we know that the secret key is available.
(gpgsm_list_keys): New arg MODE, check whether a secret key is
available. Changed all callers.
* gpgsm.c (main): New command --list-secret-keys.
* server.c (cmd_listsecretkeys): New.
(cmd_listkeys): Return secret keys with "crs" record.
* certdump.c (print_sexp): Renamed to gpgsm_dump_serial, made
global.
(print_time): Renamed to gpgsm_dump_time, made global.
(gpgsm_dump_serial): Take a real S-Expression as argument and
print the first item.
* keylist.c (list_cert_colon): Ditto.
* keydb.c (keydb_search_issuer_sn): Ditto.
* decrypt.c (print_integer_sexp): Removed and made callers
use gpgsm_dump_serial.
* verify.c (print_time): Removed, made callers use gpgsm_dump_time.
