Refactor authconfig use in ipa-client-install
    
    When certain features are being configured via authconfig, we need to
    remember what was configured and what was the state before it so that
    during uninstall we restore proper state of the services.
    
    Mostly it affects sssd configuration with multiple domains but also
    pre-existing LDAP and krb5 configurations.
    
    This should fix following tickets:
    https://fedorahosted.org/freeipa/ticket/1750
    https://fedorahosted.org/freeipa/ticket/1769