workaround for stat on root dir

Signed-off-by: shammash <shammash@autistici.org>

api/fsapi/by_artist.go

@@ -48,8 +48,12 @@ func (afs *ByArtistFilesystem) Stat(path string) (Attr, error) {
 	if len(p) == 3 {
 		return afs.getSong(p[0], p[1], p[2])
 	} else if len(p) < 3 {
+		name := "/"
+		if len(p) > 0 {
+			name = p[len(p)-1]
+		}
 		attr := Attr{
-			Name:  p[len(p)-1],
+			Name:  name,
 			IsDir: true,
 		}
 		return attr, nil