Merge the r1496127 group from trunk:

 * r1496127, r1567492, r1567494
   Fix occasional failure of checkout_tests.py 12 due to dropping the
   fractional seconds from the current time.
   Justification:
     Spurious FAILs confuse people testing the release.
     This group was back-ported to 1.8.x in http://svn.apache.org/r1567731 .
   Votes:
     +1: julianfoad, danielsh, rhuijben


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x@1605567 13f79535-47bb-0310-9956-ffa450edef68