Affected files: guides/common/modules/proc_booting-virtual-machines.adoc and guides/common/modules/proc_chainbooting-ipxe-from-pxelinux.adoc
Task: Reword the note about cloning and editing templates.
Goal: Users should always use custom pre and custom post snippets to run custom code during host registration/host provisioning.

nightly docs: https://docs.theforeman.org/nightly/Provisioning_Hosts/index-katello.html#running-custom-code-during-host-provisioning which explains the exact name the snippets must have to get picked up when Foreman rendered the templates.