Provide CorDapps to containers deployment options

[henrikr3]

Currently CorDapps are copied to the Corda Node container once it is running to the persistent storage assigned to that pod. The CorDapps should ideally be segregated.

a) Init containers
We could deploy the CorDapps to the Corda Node pod by use of init containers to install the CorDapps before the pod starts up:
https://kubernetes.io/docs/concepts/workloads/pods/init-containers/
This would essentially work as such:

• Corda Node is deployed to Kubernetes cluster
• Corda Node init container is automatically launched
• Corda Node init container starts up and downloads CorDapps assigned to be loaded to the Corda Node from a dedicated distribution site on for example Azure Storage or Amazon S3.
• Once init container has completed successfully (verifiably installed the CorDapps), the Corda Node will start up with the CorDapps already available

b) Other options could be considered as well:

• CorDapp Distribution Service (CDS) - https://github.com/corda/corda-solutions/tree/master/bn-apps/cordapp-updates-distribution
• other possibilites...

A few options could be defined in Helm charts as options that the user can select from for deploying CorDapps.