Improve debug logging around server unavailble (ditch the loop), missing contributions, mail store problems

I have been trying to track down some missing credit card transactions in Civi. Trawling through the very large log file to find these I note

1) insufficient info logged on the imap errors I see there
2) no logging of transactions rollbacks from CRM_Profile_Form
3) 70,000 + lines of errors logged during one short mysql outage because of a loop in abend