ipa-replica-install: Use configured IPA DNS servers in forward/reverse resolution check
    
    Previously, ipa-replica-install tried to check DNS resolution on the master
    being cloned. If that master was not a DNS server, the check failed.
    
    Change the check to query the first available configured DNS server.
    
    Log about the check before actually running it.
    Log in the case the check is skipped (no IPA DNS servers installed).
    
    https://fedorahosted.org/freeipa/ticket/3194