install: declare knob CLI names using the argparse convention
    
    Replace cli_name, cli_short_name and cli_positional knob arguments with a
    single cli_names argument, which allows defining one or more CLI names
    using the argparse convention ("--option" for long option name, "-o" for
    short option name and "argument" for positional argument name).
    
    Also replace cli_aliases with cli_deprecated_names which uses the same
    convention.
    
    https://fedorahosted.org/freeipa/ticket/6392
    
    Reviewed-By: Martin Basti <mbasti@redhat.com>