1970.01.01 00:00:00 is Java's "0" date-time value in milliseconds
stored as a long (64 bit.)  I'm going to switch the history tables
over to keying by such a value so I can quickly and easily persist
millisecond timestamps to the database for history sequencing and
redos.  Millisecond recording is important for ensuring that the
individual creates, updates, and deletes performed during the
servicing of a request are ordered by some unique value.  As it is
likely to take at least *some* milliseconds to perform a database
operation, sorting by the milliseconds-since-1970 value should
provide sufficient ordering to make redo logs reliable, even though
multiple database threads of data will be intermingled in the history/redo
logs.