Allow for multi-instance configuration (High bandwidth)

[Phoul]

Allow for deploying multiple relays to one host, for high bandwidth relays:

https://www.torservers.net/wiki/setup/server#systemd

tor-instance-create <name>
# torrc for new instance is in /etc/tor/instances/<name>/torrc
systemctl enable tor@<name> # create symlinks for auto-launch of the new instance
systemctl start tor@<name> 

[Sixdsn]

done here: Sixdsn#17