Archive provisioning

[gbryant-arm]

Requested feature
Being able to provision file archives instead of provisioning files one by one

Motivation
Currently files have to be provisioned one by one, which is not practical nor efficient when many files have to be transmitted.

Solutions
Archiving could be implemented as a pipelined Veracruz program (WASI or native), this program being the first one in the pipeline, before the unarchived data can be used for the actual computation.
Alternatively this could be implemented in the trusted runtime as a native module or new feature.
Since this seems to be a common use case for Veracruz, we should provide an example that implements data archiving/unarchiving.