[389-devel] Please review: Entry USN

[Noriko Hosoi]

 First cut for implementing Entry USN.
 See http://directory.fedoraproject.org/wiki/Entry_USN for the design 
details.
 This change includes a bug fix for "db2ldif -r"; event queue system was not
 shutdown before the plugins are closed, which could have crashed the 
command
 line utility.

Thanks,
--noriko