Put Tor's GPG key in /etc/apt/trusted.gpg.d/

phw said that the "init scripts tried to install Tor but it hangs while waiting for user input after executing "aptitude -y install tor tor-geoipdb". The reason seems to be aptitude's signature warning which trumps the -y option."

rransom then added that I "need to put the GPG key in a file in /etc/apt/trusted.gpg.d/".