Remove Need for FHIR Validator Local Package Cache

[alexanderkiel]

The FHIR Validator is used in a way that it needs the NPM packages under ~/.fhir/packages. That local file system dependency means that Blaze has to run as a special user having a home directory with the packages pre populated. Random User ID's that are best practise in Docker runtimes are not possible with that. We need to remove that dependency.