zsh:glog: Show pgp key instead of fingerprint

Also display a status: (From `git-show` manpage)
```
"G" for a good (valid) signature,
"B" for a bad signature,
"U" for a good signature with unknown validity,
"X" for a good signature that has expired,
"Y" for a good signature made by an expired key,
"R" for a good signature made by a revoked key,
"E" if the signature cannot be checked (e.g. missing key) and
"N" for no signature
```

.config/zsh/autoload/glog

@@ -30,7 +30,7 @@ local -a format=(
 	'Commit:      %cN %cE%Cred'      # blue commiter mail
 	'CommitDate:  %cd%Cblue'         # red commit date
 	'Signer:      %GS%Cgreen'        # signer name
-	'Fingerprint: %GF'               # pgp fingerprint
+	'Key (%G?):     %GK'             # pgp key used to sign
 	'%Creset%C(bold)'                # empty line
 	'    %s%Creset'                  # bold white subject
 	''                               # newline