Feature Request: add the ability to shuffle all cached music

[charmparticle]

current behavior: there is a shuffle limit of 100. If I cache a bunch of music, then go offline, only the first 100 songs are shuffled, while the rest are played in order.

desired behavior: when I am offline or plaing cached music, the shuffle button shuffles everything within the scope of where it was pressed, ie, all music if it was pressed in "Library", or all of my cache of an artist's discography if I'm in, say, "Radiohead", or just an album if I'm in an album.