Everything that this field contained can be computed in another way:
- path: just lookup the local target and read the path from there
- mime: can be derived from distribution and compose output type
- size: can be derived from the path
Therefore it imho doesn't make much sense to store these information multiple
times.
The store package is getting too big and convoluted, this new package
will help with separation of the compose logic from our current
implementation of the store.
The current implementation will be removed in following commits.