core: New encryption flags GPGME_ENCRYPT_ADD_RECP and _CHG_RECP.
* src/gpgme.h.in (GPGME_ENCRYPT_ADD_RECP, GPGME_ENCRYPT_CHG_RECP): New flag values. * src/engine-gpg.c (have_cmd_modify_recipients): New. (gpg_encrypt): Check availability of the feature and prepare command. * tests/run-encrypt.c (main): New options --add-recipients and --change-recipients.
- GnuPG-bug-id: T1825