[WIP] various improvements

• fixes #1
• replace python2 by python3
• move to master branch again, allowing to remove the basilisk branch eventually
• remove unneeded, old scripts (genauth.sh, init_stratumkey.sh, ... ?)
• replace manual fiddling with the sshd log by journalctl operations
• who am i -> whoami in bootstrap.sh"
• add set -e in all scripts