Unify file creation for the single-file and multi-file cases.
Unify file creation for the single-file and multi-file cases.

This fixes a bug where we were not creating the download directory for
the single-file case.

Dataman-Cloud/Taipei-Torrent,nictuku/Taipei-Torrent,zyxar/taipei,beni55/Taipei-Torrent,nictuku/Taipei-Torrent,ansonwzj/CPSC416Taipei,ansonwzj/CPSC416Taipei,rakoo/rakoshare,rakoo/rakoshare,FlexibleBroadband/Taipei-Torrent,beni55/Taipei-Torrent,Dataman-Cloud/Taipei-Torrent,FlexibleBroadband/Taipei-Torrent