by specifying a non-existent ceph-ansible directory
or not specifying it at all.
Lets user provide extra packages before running ceph-ansible.
Since linode-launch.py will not re-create existing VMs,
and since pre-config.yml is idempotent and doesn't take long,
you can just rerun launch.sh with the correct
ceph-ansible directory after extra packages are provided
by specifying a non-existent ceph-ansible directory or not specifying it at all. Lets user provide extra packages before running ceph-ansible. Since linode-launch.py will not re-create existing VMs, and since pre-config.yml is idempotent and doesn't take long, you can just rerun launch.sh with the correct ceph-ansible directory after extra packages are provided