Use sleep with value less than 1 (e.g. 0.5)

These changes are required to support NetBSD.
1) Use standard -p option for time command in test17.35 instead of
GNU specific format string to fetch the elapsed (real) time.

2) Adjust date command calls in test22.1 to use short option
(--date -> -d), and move options before arguments. NetBSD,
unlike Linux, disallow non standard order.

3) Use standard -R option instead of -r for cp command in test30.1.

bug 1649

bug 1642

Correct list of unavailable nodes reported in a job's "reason" field when
that job can not start.
bug 1614

bug 1684

bug 1679

Bug 1679

switch/cray: Revert logic added to 14.11.6 that set "PMI_CRAY_NO_SMP_ENV=1"
if CR_PACK_NODES is configured.
bug 1585

preempt/job_prio plugin: Implement the concept of Warm-up Time here. Use
the QoS GraceTime as the amount of time to wait before preempting.
Basically, skip preemption if your time is not up.

Bug 1627