Fix - default cluster directory `~/cluster-defaults` contains another directory that is not copied by `cp` command

Created by: matofeder

Since #432 the default dir ~/cluster-defaults contains containerd dir with default containerd registry host/cert files. Script create_cluster.sh copy this default directory to the cluster-specific directory using cp -p command. As this command does not contain -r option, the command failed to copy containerd dir into cluster-specific directory.