Add support for job suspend/resume.

NEWS

doc/html/faq.shtml

doc/html/selectplugins.shtml

doc/man/man1/sacct.1

doc/man/man1/scancel.1

doc/man/man1/scontrol.1

doc/man/man1/smap.1

doc/man/man1/squeue.1

doc/man/man3/slurm_resume.3

slurm/slurm.h.in

src/api/job_info.c

src/api/signal.c

src/common/node_select.c

src/common/node_select.h

src/common/slurm_protocol_defs.c

src/common/slurm_protocol_pack.c

src/plugins/select/bluegene/plugin/select_bluegene.c

src/plugins/select/cons_res/select_cons_res.c

src/plugins/select/linear/select_linear.c

src/scancel/opt.c