* g10/dek.h (DEK): Turn fields use_mdc, algo_printed and symmetric
into single bit vars.  Make sure they are always set to 1 or 0.
(DEK): New field use_aead.
* g10/options.h (struct opt): New field force_aead.
* g10/pkclist.c (select_aead_from_pklist): New.
* g10/gpg.c (oForceAEAD): New const.
(opts): New options "--force-aead".
(main): Set new option.
* g10/encrypt.c (use_aead): New.
(encrypt_simple): Implement new flags DEK.use_aead.
(encrypt_crypt): Ditto.
(encrypt_filter): Ditto.
* g10/sign.c (sign_symencrypt_file): Ditto.