Rewrite it in Go

[louisroyer]

• Get rid of jinja and GNU-make and rewrite this as a Go program
• Generate a compose file from a configuration file (number of ues/ran/areas, dataplane/controlplane used, etc.)
• Can be overridden by a compose.override.yaml file to add new services or edit containers values manually
• Builtin commands instead of GNU-make's hacks
• scenarios becomes bash/python scripts