Currently there's no way to truly include modules within another module, only express dependency on them. We need both of these mechanisms because

• we need to build stacks such as the Generational Core (inclusion) and
• we need to build non-container application modules against the Generational Core (dependency)

Modules should be another component type, just like RPMs. They should reference dist-git hashes, too, and they should support component build order as well.