Harmonization of dependencies and data-dependencies

Estimate: Medium-Large
mostly work on design and coordination, medium estimate for implementation effort

Summary
We provide the API / interface that dpm needs to author and damlc needs to consume - (YAML schema). MoonLabs (or Infra team) could implement the spec. Language team preferred to make changes that consume the spec.

Status: Needs significant investment in review, feedback, and detailing potential implementation plan