- Added support for embeded cover. Demuxer just need to fill psz_arturl meta
field to "attachment://NAME" where NAME is an attachment filename (returned by DEMUX_GET_ATTACHMENTS) - Lock input_item_t every time we access p_meta fields (there is still a problem as playlist code does not always do so...). - Do not preparse item we have already played. - Wait that the current playing item is meta parsed before fetching its cover.