Log message:
Import stem-1.7.0, nyx-2.0.4, and sbws-0.8.0 from the Tor Project.

stem-1.7.0: Python library for controlling the tor daemon
nyx-2.0.4: curses monitor for the tor daemon
sbws-0.8.0: bandwidth scanner

nyx is a standalone application, so give it a meta-package net/nyx
with no py- prefix.

sbws is a standalone application too but only for designated Tor
plumbers, not for ordinary users, so leave it as py-sbws.