filesystem include updates, duplicate group suppression, cleanups, filesystem whiteout support (unionfs), bidir popen().
This will make a number of things easier in the future, as well as (finally!) avoiding the Id-smashing problem which has plagued developers for so long. Boy, I'm glad we're not using sup anymore. This update would have been insane otherwise.
Added $Id$. Obtained from: 4.4BSD-Lite2