* Remove extraneous passing of transaction set hashes
* Remove recentPositions_. InboundTXs does the job now
* Move responsibility for sending "have TX set" out of consensus
Replace Journal public data members with member function accessors
in order to make Journal lighter weight. The change makes a
Journal cheaper to pass by value.
Also add missing stream checks (e.g., calls to JLOG) to avoid
text processing that ultimately will not be stored in the log.
* Move InboundTransactions to app/ledger
* Move TransactionAcquire to app/ledger
* Move LocalTxs to app/ledger
* Move Transaction to app/misc
* Move TransactionMaster to app/ledger