dirmngr: Add framework to implement a fake CRL feature.
* dirmngr/fakecrl.c: New. * dirmngr/dirmngr.h (opt): Add fake_crl. * dirmngr/dirmngr.c (enum cmd_and_opt_values): Add oFakeCRL. (opts): Add "fake-crl" (parse_rereadable_options): Set opt.fake_crl. * dirmngr/server.c (cmd_isvalid): Take care of fakce CRLs.