[Desktop][Browse] Make distinction between EDM subgenres

[Martijn96]

This has been bugging me me for a while so here goes. Currently in the Genres & Moods screen there are all sorts of music genres: Pop, Rock, Hip Hop; and additionally some social movement categories like EQUAL and Pride.

However, still there exist no categories for EDM subgenres and they are all thrown on one big heap in Dance/Electronic. Why are there no categeries for Trance, Techno, House and so on? All immensely popular genres with probably millions of listeners. If you are going to add a subcategory named EQUAL, which while I support the movement has not much to do with music IMO, please consider adding this too.