#79 would be nice to be able to sort by column in the downloads

[ras_u_ras_t]

Feature request:

In the download pane, I'd like to be able to sort the listings by selecting the
column headers. I kindof thought that was default behaviour of this widget,
but I guess not.

Other than a bit of confusion over how to do things, this seems to work pretty well, way better than iTunes which was driving me up the wall, thanks a lot!