FTP: Support for multiple up/download threads

Aside from my request/bugbear related to instant file/tag searching, my other major bugbear for DOpus is FTP support. It's great apart from one thing - it's very slow due to only using a single up/download thread.

If I have to upload lots of files to a web server, it's extremely slow compared to something like FileZilla which can use up to 10 up/down threads (but then I lose the rest of the Opus goodness).

Can you add multiple up/down thread support for FTP.