* use tls for nats connections
* add config options for nats client tls config
* add nats tls config to CI
* add function to create a certpool
* add option to provide a rootCA to validate the server's TLS certificate
* add option to provide a rootCA to validate the server's TLS certificate
* add option to provide a rootCA to validate the server's TLS certificate
* add option to provide a rootCA to validate the server's TLS certificate
* configure nats clients in reva to use tls