[sugar] datastore use cases for activities

[Walter Bender]

> > A similar use case would be for the upload file dialog in Browse. In
> > this case all entries that have an associated file should be presented
> > to the user. The user should be able to search, filter and sort just
> > like in the journal in order to find the entry that will be uploaded.
>
> Activity-provided file selection boxes are explicitly not supported by
> the current Bitfrost spec.

How would browsing (read-only) through the Library
(/home/olpc/Library) work, for example? Or letting the children browse
(read-only) through the root file system?

-walter