As part of investigations for T75, @olasd noticed that revisions being added by the SVN loader (currently running on Google Code SVN dumps) reach the Postgres DB with an off-by-1us (microsecond) timestamp, resulting in additional inconsistent checksums.

According to early investigations this happens after passing through our model module, on the way to the database.

This should be fixed ASAP, and certainly before restarting the SVN loader tasks