* keyedit.c (keyedit_menu): Prompt for subkey removal for both secret and

public subkeys.

* keylist.c (list_keyblock_print), keyedit.c (show_key_with_all_names):
Show the revocation date of a key/subkey, and general formatting work.

* packet.h, getkey.c (merge_selfsigs_main, merge_selfsigs_subkey,
merge_selfsigs): Keep track of the revocation date of a key.

* keydb.h, keyid.c (revokestr_from_pk): New function to print the
revocation date of a key.

g10/packet.h

@@ -196,6 +196,7 @@ typedef struct {
     u32     timestamp;	    /* key made */
     u32     expiredate;     /* expires at this date or 0 if not at all */
     u32     max_expiredate; /* must not expire past this date */
+    u32     revokedate;     /* revoked at this date */
     byte    hdrbytes;	    /* number of header bytes */
     byte    version;
     byte    selfsigversion; /* highest version of all of the self-sigs */