HAPI Dockerfile with insertion point for our script

[lp]

Why

We need a starter Dockerfile, the meeting point of the HAPI server & our bootstrapping script execution environment

What was done

• [x] assemble a Dockerfile featuring a working HAPI server
• [x] Install hapi-fhir-cli in that Docker
• [x] control the ENTRYPOINT for both HAPI server & bootstrapping script