Add AlwaysWriteMp3sGenresAsText option

[IJabz]

Add alwaysWrite Mp3s Genres as text option like we have for mp4s. Without this if using the generic interface it always writes genres as numbers if can find a match for the genre text passed in the the list of standard genres by searching either for name or id.

But some applications only understand genres as text so we need a way to always write genres as test.

[IJabz]

Fixed (jaudiotagger 2.2.3)