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