Alcina metamodel - contexts

[nevella]

• Registry becomes context aware (DelegatingRegistryAdapter) - Registry.push(), Registry.pop()
• AbstractContextProvider - single- or multi-threaded context support:
  • LooseContext
  • Registry
  • PermissionsManager
  • TransformManager
  • ContextResolver

App startup sets the contextproviders (if not defaults). ContextProviders generate a ContextFrame from a parent, and manage (possibly multiple) ContextStack variables