- RedHat systems: use "dnf" instead of "yum" when available - add openssl to the list of required pacckages (for NaviServer 4.9.12)
- RedHat systems: use "dnf" instead of "yum" when available
- add openssl to the list of required pacckages (for NaviServer 4.9.12)

gustafn/install-ns,tekbasse/install-ns