Ticket 49277 - improve out of box system tuning for EL7
    
    Bug Description:  We asked admins to run dsktune and others tools
    but with the move to "pet" and automation, we have no guarantee
    an admin will tune their system.
    
    Fix Description:  We should provide sane defaults to systemd
    and sysctl that enables DS to perf "great" out of the box. This
    is a combination of my sysadmin expirence and our performance
    tuning guide.
    
    https://pagure.io/389-ds-base/issue/49277
    
    Author: wibrown
    
    Review by: mreynolds (Thanks!)