Ticket 50230 - improve ioerror msg when not root/dirsrv
    
    Bug Description: When not running as root or dirsrv, improve the clarity
    of the error messages as the previous messages were misleading.
    
    Fix Description: Improve the exception handling and messages.
    
    https://pagure.io/389-ds-base/issue/50230
    
    Author: William Brown <william@blackhats.net.au>
    
    Review by: mhonek