Add '%N'-format for pretty-printing commit notes

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/pretty-formats.txt

@@ -123,6 +123,7 @@ The placeholders are:
 - '%s': subject
 - '%f': sanitized subject line, suitable for a filename
 - '%b': body
+- '%N': commit notes
 - '%Cred': switch color to red
 - '%Cgreen': switch color to green
 - '%Cblue': switch color to blue

pretty.c

@@ -702,6 +702,10 @@ static size_t format_commit_item(struct strbuf *sb, const char *placeholder,
 	case 'd':
 		format_decoration(sb, commit);
 		return 1;
+	case 'N':
+		get_commit_notes(commit, sb, git_log_output_encoding ?
+			     git_log_output_encoding : git_commit_encoding, 0);
+		return 1;
 	}
 
 	/* For the rest we have to parse the commit header. */