Typo, forgotten debug string and a missing comment

id3v2metadata.go

@@ -116,7 +116,7 @@ func (m metadataID3v2) Disc() (int, int) {
 func (m metadataID3v2) Lyrics() string {
 	t, ok := m.frames[frames.Name("lyrics", m.Format())]
 	if !ok {
-		return "toto"
+		return ""
 	}
 	return t.(*Comm).Text
 }

tag.go

@@ -87,9 +87,10 @@ type Metadata interface {
 	// Disc returns the disc number and total discs, or zero values if unavailable.
 	Disc() (int, int)
 
-	// Picture returns a picture, or nil if not avilable.
+	// Picture returns a picture, or nil if not available.
 	Picture() *Picture
 
+	// Lyrics returns the lyrics, or an empty string if unavailable.
 	Lyrics() string
 
 	// Raw returns the raw mapping of retrieved tag names and associated values.