TRQ-2408 scan_for_terminated needs to be on its own thread.

We were able to solve this problem without putting scan_for_terminated
on its own thread. We modified scan_for_terminated so it would not
update every job each time scan for terminated had been called. It
now only updates jobs that are finished and it only updated finished
jobs one time.

Conflicts:

	src/include/pbs_job.h
TRQ-2749 - Add --with-boost-path option to configure. Also confirm that boost
has been installed and meets the minimum version requirement before building.
Fix a regression with job usage information not being passed to the epilogue.
TRQ-2759. Fix a problem with cput getting cut off.
TRQ-2760. Fix a pbsnodes -n regression
Merge branch 'master' into feature/insight (run by anonymous)