Will now track both the position inside the journal file and the position in the scratch file
* Flushing to log should not actually touch the journals, we are already dealing with them in the scratch, and we should have the page table in memory
* Free scratch pages
* Will read (just tx header) from the log file.
DeleteOnClose for journal files
Various fixes to complete the previous work
Better behavior when we do the write in a sync manner
Increase size of work that we are allowed to merge.