Merge from vendor branch TNF:

Merge from vendor branch TNF:
Import dtorrent-3.3.2 as net/dtorrent.
Based on packaged by Jeff Woodall and provided via PR#43254.

Enhanced CTorrent is a BitTorrent console client written in C/C++. Like
ctorrent, which it is based on, high performance with minimal system
resources and dependencies is a priority. Enhanced CTorrent adds additional
features like dynamic adjustments and fixes several bugs in the original
ctorrent client (obsolete and marked EOL in pkgsrc repository).

More info at: http://www.rahul.net/dholmes/ctorrent/