Secure and harden Elasticsearch.

1. Stop people from shutting down your node
```action.disable_shutdown: true```
2. Stop using the root user.
This required updatinng `/etc/pam.d/su` to include *pam_limits.so*
Updated /run.sh to su as USER elasticsearch does not provide the same environment as su - does

Signed-off-by: Scott M. Likens <scott@likens.us>
add crane.json