Implement --read-news (off by default)

Turn off news-reading by default when --ask, and instead make it an
option --read-news.

Apparently making --ask a bit more interactive was "goddamn stupid" and
ruined the lives of several Gentoo developers. Props to Michał who
predicted this all along.

ACKed-by:      Brian Dolbec       <dolsen@gentoo.org>
Signed-off-by: Alexander Berntsen <bernalex@gentoo.org>
Fix travis test failures due to setup.py installing future sbin scripts in bindir