Improve differences between xCAT and confluent

[Obihoernchen]

Features in xCAT, but not in Confluent:

• missing DNS
  • Alternative: confluent2hosts + dnsmasq or noderun + external DNS
• no DHCP for non PXE clients, just used for PXE/HTTP boot
  • Alternative: Use your own DHCP server in parallel
• no makentp
• no remote syslog cfg

https://xcat2.github.io/confluent-docs/miscellaneous/confluentvxcat/