Deps.sh not supporting sudoless installations

[mkowalski]

Currently https://github.com/netsec-ethz/scion-apps/blob/master/deps.sh#L15 contains an explicit call to sudo which makes it impossible to execute the script in a sudoless environments, i.e. inside a docker.

This is a similar issue to scionproto/scion#3065, i.e. this should be either explicitly stated in the docs if the environment has to be very specific (OS version, non-root user, whatever else) or the scripts should try to cover as generic use as possible.

Currently neither this nor scionproto docs say it's required to be non-root in a non-dockerized setup what is nowadays a more and more popular configuration.