In FHIRPersistenceJDBCImpl connect transactionDataImpl to transaction provider framework

[punktilious]

Currently transactionDataImpl receives transaction event callbacks from JTA UserTransaction. However, transactions in unit tests are managed differently, and so the transaction framework needs to be updated to feed similar transaction events to transactionDataImpl when executing unit tests.

Because we no longer actually use the transactionDataImpl to hold any of the data collected during a transaction (it's now held in FHIRPersistenceJDBCImpl), there is an opportunity to clean some of this up and hopefully simplify the code).

[lmsurpre]

@punktilious do we still need this one?

[punktilious]

I'm going to reshape this one because there's some cleanup that we can do here because we now hold all the data collected during a transaction in the FHIRPersistenceJDBCImpl.