Fact: dhcp_servers
Purpose:
Return the DHCP server addresses for all interfaces as a hash. If the interface that is the default gateway is dhcp assigned, there will also be a 'system' entry in the hash.
Resolution:
Parses the output of nmcli to find the DHCP server for the interface if available
Caveats:
Requires nmcli to be available and the interface must use network-manager.