488d01c py3: create DNS zonefile: use textual mode

1 file Authored by mbasti 2 years ago , Committed by jcholast 2 years ago ,
    py3: create DNS zonefile: use textual mode
    
    Also code was rewritten to use NamedTemporaryFile with context
    
    https://fedorahosted.org/freeipa/ticket/4985
    
    Reviewed-By: Jan Cholasta <jcholast@redhat.com>