pcp

Rework PATH handling in all PCP shell scripts (via pcp.env)
to address some issues disussed on the mailing list...

The explicit setting of LD_LIBRARY_PATH on Solaris gives
me some security concerns (this is used by the PCP start
and cron scripts, so is often executed as root) - it's
better to do that stuff through the /etc/ld.so.conf.d/
equivalent in Solaris, not here. The Solaris-specific
part then specifies /usr/local/bin, which is respecified
later - a bit odd.

Also, theres no way to extend the PATH seen by PMDAs. I
hit a situation yesterday where it would've been really
useful to have a configuration hook there.

Finally, every time we run PCP scripts, we potentially
have to go off and stat an ever-increasing number of
directories, many being there for other platforms, which
just isn't a clean design.