TRQ-2814: set pbsnodes to job-exclusive once the node is being used regardless whether it still has any processor free.

Conflicts:

	src/server/node_func.c

Conflicts:

	src/server/node_func.c
	src/server/test/node_manager/test_uut.c
TRQ-2814: fixed a wrong statement from merge.
TRQ-2814 - Improved prior checkin, so we don't need a restart of pbs_server for job_exclusive_onuse setting change.

Conflicts:

	src/server/node_func.c

Conflicts:

	src/server/node_func.c
	src/server/test/node_manager/test_uut.c
Fixed broken unit tests.