wks: New option --check for gpg-wks-client.
* tools/call-dirmngr.c (wkd_get_key): New. * tools/gpg-wks-client.c (aCheck): New constant. (opts): New option "--check". (main): Call command_check. (command_check): New.
- GnuPG-bug-id: T2866
- Signed-off-by: Werner Koch <wk@gnupg.org>