core: Enhance gpgme_data_identify to detect binary PGP messages.
* src/gpgme.h.in (GPGME_DATA_TYPE_PGP_ENCRYPTED): New. (GPGME_DATA_TYPE_PGP_SIGNATURE): New. * src/data-identify.c: Add enum for OpenPGP packet types. (buf32_to_ulong): New. (next_openpgp_packet): New. Based on the gnupg/kbx/keybox-openpgp.c implementation and relicensed to LGPL by g10 Code. (pgp_binary_detection): New. (basic_detection): Call pgp_binary_detection instead of returning unknown.
- Signed-off-by: Werner Koch <wk@gnupg.org>