Move transactions data to partitioned table

[galgitron]

The way the ledger and transaction tables are laid out, virtually all queries are going to be very expensive because of the table scans. If you were to merge the ripple time, correct CloseTime, and the remainder of the transaction table into a "partitioned table" (and dropping the original transaction table), it would then be possible to search by date in a near-index-like efficiency, radically reducing the cost of querying when dates are involved.

Possible shortest/cheapest path to accomplish this:
https://stackoverflow.com/questions/38993877/migrating-from-non-partitioned-to-partitioned-tables/43130999#43130999