EBML: Add mapping for ItemKey::TrackSubtitle

Author: Serial-ATA

lofty/src/ebml/tag/generic.rs

@@ -62,6 +62,7 @@ matroska_mapping_tables!(
 
 		// Titles
 		"TITLE"               <=> TrackTitle,
+		"SUBTITLE"            <=> TrackSubtitle,
 
 		// Nested Information
 		"SORT_WITH"           <=> TrackTitleSortOrder,

lofty/src/tag/utils.rs

@@ -4,7 +4,7 @@ use crate::file::FileType;
 use crate::macros::err;
 use crate::tag::{Tag, TagType};
 use crate::util::io::{FileLike, Length, Truncate};
-use crate::{aac, ape, flac, iff, mpeg, musepack, wavpack};
+use crate::{aac, ape, ebml, flac, iff, mpeg, musepack, wavpack};
 
 use crate::id3::v1::tag::Id3v1TagRef;
 use crate::id3::v2::tag::Id3v2TagRef;
@@ -34,7 +34,7 @@ where
 		FileType::Aac => aac::write::write_to(file, tag, write_options),
 		FileType::Aiff => iff::aiff::write::write_to(file, tag, write_options),
 		FileType::Ape => ape::write::write_to(file, tag, write_options),
-		FileType::Ebml => todo!("write EBML tags"),
+		FileType::Ebml => ebml::write::write_to(file, tag, write_options),
 		FileType::Flac => flac::write::write_to(file, tag, write_options),
 		FileType::Opus | FileType::Speex | FileType::Vorbis => {
 			crate::ogg::write::write_to(file, tag, file_type, write_options)