Show transaction id after starting a transaction and in statement summary

[guyilin-amazon]

After we start a transaction by typing begin or start transaction, the Shell would prompt qldb *> . The * denotes there is an active transaction which does not include the transaction id.

We could add the transaction id information in the prompt after starting a transaction, which is similar to the Python Shell. We could also add the id to the statement summary which currently is {} document/s in bag (read-ios: {}, server-time: {}ms, total-time: {}ms). So we could use the id for future queries.