Where arg can be like -flag or --flag as well as the classic Windows notation /flag too.GNU-style hyphens are also accepted in place of underscores.
When some argument has the appropriate suffix (ie. ".ace" or ".ACE"), the ace parser is automatically launched in order to parse this configuration file. The caller is then notified that we are now in ACE mode (the result is True). When we are in ACE mode, remaining allowed arguments are automatically handled.