Add message at top of global_ignore to dissuade local edits

ROOT/etc/chem-zfs-backup-server/zfs-rsync.d/global_ignore

+# Please don't edit this file directly!
+# Instead, modify the packaged version as provided by our backup-scheduler repo
+# We flag this as a config file, so if it's edited here we'll get prompted about
+# differences when upgrading the package version
+
 # Files to be ignored in rsnapshots
 /dev/
 /proc/