Fix various bugs in access log filtering:
* OPENDJ-1429: Access log filtering criterion request-target-dn-not-equal-to does not work
* OPENDJ-1432: Access log filtering criterion on etime property does not work
* OPENDJ-1433: Access log filtering criterion on result code property does not work
* OPENDJ-1434: Access log filtering criteria user-dn-not-equal-to does not work
* OPENDJ-1435: Access log filtering criteria user-is-not-member-of does not work.
Also added unit tests. Use a single commit because a) the fixes are very small and closely related, and b) some of the bugs have a common cause.