gpg: Prepare for listing last_update and key origin data.

* g10/keylist.c (list_keyblock_colon): Add empty fields 19 and 20.

--

We add them now to early catch error in parsers which arbitrary limit
the number of fields in --with-colon listings.

Signed-off-by: Werner Koch <wk@gnupg.org>

doc/DETAILS

@@ -149,6 +149,7 @@ described here.
     the regular expression value, quoted as in field 10.
 
 *** Field 10 - User-ID
+
     The value is quoted like a C string to avoid control characters
     (the colon is quoted =\x3a=).  For a "pub" record this field is
     not used on --fixed-list-mode.  A UAT record puts the attribute
@@ -156,6 +157,7 @@ described here.
     subpacket size.  In gpgsm the issuer name comes here.  A FPR
     record stores the fingerprint here.  The fingerprint of a
     revocation key is stored here.
+
 *** Field 11 - Signature class
 
     Signature class as per RFC-4880.  This is a 2 digit hexnumber
@@ -227,6 +229,21 @@ described here.
     - 8  :: The key is compliant with RFC4880bis
     - 23 :: The key is compliant with compliance mode "de-vs".
 
+*** Field 19 - Last update
+
+    The timestamp of the last update of a key or user ID.  The update
+    time of a key is defined a lookup of the key via its unique
+    identifier (fingerprint); the field is empty if not known.  The
+    update time of a user ID is defined by a lookup of the key using a
+    trusted mapping from mail address to key.
+
+*** Field 20 - Origin
+
+    The origin of the key or the user ID.  This is an integer
+    optionally followed by a space and an URL.  This goes along with
+    the previous field.  The values are not yet defined.
+
+
 ** Special fields
 
 *** PKD - Public key data

g10/keylist.c

@@ -1308,7 +1308,9 @@ list_keyblock_colon (ctrl_t ctrl, kbnode_t keyblock,
     }
   es_putc (':', es_stdout);		/* End of field 17. */
   print_compliance_flags (pk, keylength, curvename);
-  es_putc (':', es_stdout);		/* End of field 18. */
+  es_putc (':', es_stdout);		/* End of field 18 (compliance). */
+  es_putc (':', es_stdout);		/* End of field 19 (last_update). */
+  es_putc (':', es_stdout);		/* End of field 20 (origin). */
   es_putc ('\n', es_stdout);
 
   print_revokers (es_stdout, pk);
@@ -1358,7 +1360,9 @@ list_keyblock_colon (ctrl_t ctrl, kbnode_t keyblock,
 	    es_fprintf (es_stdout, "%u %lu", uid->numattribs, uid->attrib_len);
 	  else
 	    es_write_sanitized (es_stdout, uid->name, uid->len, ":", NULL);
-	  es_putc (':', es_stdout);
+	  es_fputs (":::::::::", es_stdout);
+          es_putc (':', es_stdout);	/* End of field 19 (last_update). */
+          es_putc (':', es_stdout);	/* End of field 20 (origin). */
 	  es_putc ('\n', es_stdout);
 #ifdef USE_TOFU
 	  if (!uid->attrib_data && opt.with_tofu_info