Design CLI

[Strongground]

Current implementation uses python.argparse module. It offers simple commands like "-v" for verbose output, standard "--help" page and can easily be expanded. It lives in "avorion_mm_cli.py" and calls appropriate methods of AvorionModManager instance from "avorion_mm.py".

This is a working solution in proposal state and open to discussion.
Also consider a interactive solution and review for cross platform compatibility when doing so.