Add 'ipa localenv' subcommand
    
    ipa local-env simply dumps all values from api.env as sorted key="value"
    pairs. It's a convenient helper for debugging and to write tests for
    e.g. PR #182.
    
    https://fedorahosted.org/freeipa/ticket/6490
    
    Signed-off-by: Christian Heimes <cheimes@redhat.com>
    Reviewed-By: Martin Basti <mbasti@redhat.com>
    Reviewed-By: Martin Babinsky <mbabinsk@redhat.com>