Add background discussion for the assessment questions

[fdevaulx]

It might be helpful to have a background discussion for some of the assessment questions in phase 1. For example on question 4 – there have been a lot of interesting developments here but it might be helpful to provide a comparison matrix or background of blockchain vs distributed databases / ledgers to give more context. For example, we’re exploring some POCs with Google Spanner (globally distributed DB as a Service) and Cockroach DB (open-source Spanner competitor) that are have some clear pros and cons vs blockchain.