#23 Add FULL ID3 v2.4 support

[boutros4j]

As far as I can see, id3lib doesn't support v2.4 tags fully.

Can oyu please add that support, it is vital (together with the already requested Unicode support)!

-b4j

[Pander]

Please support v2.4, see e.g. https://sourceforge.net/p/id3v2/bugs/52/