Add to Web-seed

Torrent file:
Server filename base:

When using a single-file torrent, filesystem base must be the exact filename of what is being downloaded.

When using multi-file torrents, specify the pathname of the directory that contains the base of the directory. BitTorrent adds an extra directory based on what the torrent file says is used. This script does not. Oh, and use forward-slashes / as a separator.