Save and propose to reuse previous labels

[Matth7878]

It would be really useful if transdrone could remember what labels you have been using. When adding one you should be able to pick one from your previous used one.

Right now I often have to tap anew the same label. It's especially usefull with Qbittorrent which move your torrent using torrent label. (And it's why it's important not to mistype)