Support for Write Ahead Log

If/When Tempus is receiving Telemetry data messages when the server it is running on loses power. Upon restart, that Tempus will need to know what message it was processing and if it succeeded, half-succeeded, or failed.

A write-ahead log should be used so Tempus the can check this log and compare what it was supposed to be doing when it unexpectedly lost power to what was actually done. This comparison let Tempus decide to undo what it had started, complete what it had started, or keep things as they.