add transaction uuid and timestamp to every asset state
add transaction uuid and timestamp to every asset state

The transaction uuid and timestamp match those n the blockchain itself
and can generally be used in lightweight analytics as a reliable *time
of arrival* for events.

**Note that this commit breaks trade lane compatibility with the initial
Bluemix deployment of Hyperledger.**

ibm-watson-iot/blockchain-samples,ibm-watson-iot/blockchain-samples,ibm-watson-iot/blockchain-samples,ibm-watson-iot/blockchain-samples