Prepare support with durable history: implement changes to prepare and commit/abort

Implement changes to support eviction of prepared and committed prepared updates. Since prepare and commit APIs are already implemented, this ticket is meant to:

• when prepare is called, the current committed record needs to be written to the history store.
• make sure that prepared and committed updates are formatted correctly in the cells of the data files.
• ensure that prepared and committed cells that are read from the data files create the appropriate update records.
• when abort is called on a prepared record, the corresponding commit record in the history store must be removed.