__pmBoundaryOptions(): Streamline determination of boundares.
__pmBoundaryOptions(): Streamline determination of boundares.

For multi-archive context, need only examime the first and last
archive.

wuliming/pcp,adfernandes/pcp,wuliming/pcp,adfernandes/pcp,wuliming/pcp,wuliming/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,wuliming/pcp,wuliming/pcp,adfernandes/pcp,wuliming/pcp,wuliming/pcp,adfernandes/pcp