Read-set is missing versioning

[g2flyer]

Describe the bug

As unearthed during discussion on "FPC externalized endorsement validation" (see comments in proposal), the current implementation lacks versioning info in the read-set signed by the enclave. This can potentially leave to state corruption.

With a TLCC, simply adding the version number from the peer should be sufficient. However, to also enable "FPC without Trusted Ledger", it seems be better to use the hash of the value as the version, either as replacement or in addition to version number, depending on how easy/in-expensive it is in TLCC to get the value and hash it.

[g2flyer]

versioning if single keys done in #501, For composite keys, it is not yet implemented but fails fail-safely (note composite key is not supported in FPC Lite/1.0)

[g2flyer]

close this as #506 covers more details of the remaining issue to be done