GitLab

Also add no checkpoint parameter

This sets mac address using ip set link mac.

for no_simbricks experiments

This changed a while ago in one of the refactoring steps so some of the scripts
were broken.

- adds description for netperf experiment
- reformat local.py
- reformat results/netperf.py

- classes ExpEnv and ExpOutput had to be moved to prevent circular imports
- reformat common.py