Feature Request: Add option for RB2DX (Rock Band 2 Deluxe) RB3 genres support when converting songs

[EuroMIX2]

RB2DX (Rock Band 2 Deluxe) mod offers support for more genres than vanilla RB2 does. Adding an option to Onyx (when converting and/or a global toggle) which allows for genres unsupported by RB2 normally, and changed to other supported genres when converting, to instead use the supported RB3 genres in RB2DX.

The following genres would be included:

(hardrock "Hard Rock")
(jrock "J-Rock")
(fusion "Fusion")
(latin "Latin")
(classical "Classical")
(inspirational "Inspirational")
(world "World")
(hiphoprap "Hip-Hop/Rap")
(reggaeska "Reggae/Ska")
(rbsoulfunk "R&B/Soul/Funk")
(popdanceelectronic "Pop/Dance/Electronic")