tag: added support for MusicBrainz tags

Added all important id tags from the MusicBrainz wiki:

 http://musicbrainz.org/doc/MusicBrainzTag

This should automatically enable its suport in the vorbis and flac
decoder plugins.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/tag.h b/src/tag.h
index 0c525b24..ccaf301d 100644
--- a/src/tag.h
+++ b/src/tag.h
@@ -39,6 +39,12 @@ enum tag_type {
 	TAG_ITEM_PERFORMER,
 	TAG_ITEM_COMMENT,
 	TAG_ITEM_DISC,
+
+	TAG_MUSICBRAINZ_ARTISTID,
+	TAG_MUSICBRAINZ_ALBUMID,
+	TAG_MUSICBRAINZ_ALBUMARTISTID,
+	TAG_MUSICBRAINZ_TRACKID,
+
 	TAG_NUM_OF_ITEM_TYPES
 };