pgcrypto: PGP armor headers

Hi,

Currently there's no way to generate or extract armor headers from the
PGP armored format in pgcrypto. I've written a patch to add the
support. For example:

local:marko=#* select armor('zooka', array['Version', 'Comment'],
array['Created by pgcrypto', 'PostgreSQL, the database']);
armor
-----------------------------------
-----BEGIN PGP MESSAGE----- +
Version: Created by pgcrypto +
Comment: PostgreSQL, the database+
+
em9va2E= +
=D5cR +
-----END PGP MESSAGE----- +

local:marko=#* select pgp_armor_header(armor('zooka', array['Version',
'Comment'], array['Created by pgcrypto', 'PostgreSQL, the database']),
'Comment');
pgp_armor_header
--------------------------
PostgreSQL, the database
(1 row)

.marko