Renamed TestUI to Test. This is less confusing for the component name.
UI Components are now aggregated in packages, together with Queries and Commands. These packages are then imported by the UI of the app, which parses them through the PackageRegistry, which is used now as a central place for all components, commands and queries.
Added a comment for later
Renamed PackageRegistry to something more generic UIRegistry
Let UIRegistry to what QueryManager used to do. This makes more sense.
Updated todo