ipa-replica-manage: use `server_del` when removing domain level 1 replica
    
    `ipa-replica-manage del` will now call `server_del` behind the scenes when a
    removal of replica from managed topology is requested. The existing removal
    options were mapped on the server_del options to maintain backwards
    compatibility with earlier versions.
    
    https://fedorahosted.org/freeipa/ticket/5588
    
    Reviewed-By: Martin Basti <mbasti@redhat.com>