Remove Futurama copyright pictures of SLURM from index.html. Additional
level of document hierarchy added for clarity.

1. New srun argument --mpi=<type>  (e.g. "--mpi=lam")
2. New environment variable set SLURM_TASKS_PER_NODE
3. Launch a single task per node if --mpi=lam

modifications were relatively minor - mostly changes in function
names or arguments.

(gnats:346)

  (it was inappropriately going to DRAINING state).

  to prevent things getting hosed if the table is re-read on SIGHUP.

  see memory leaks.

  (it grows anyway).
Fix state read logic to better handle error conditions.

Fix update node RPC to handle reason field change without state change.
  State was being handled as type int instead of uint16_t so NO_VAL check
  was not working properly.

"Scontrol abort" works. It was leaving a hung pthread due to a recent
   change.
Fix a couple of potential memory leaks
"switch_type" has been added to config data structure, un/pack, etc,
   but not yet reported to the user or documented yet.
The plugins now use function calls to get a their type and plugin directory
   from a common data structure rather than individually reading and
   parsing the configuration file.

line for greater clarity.

  (as well as the reverse) in all qsw code.

 - move elanhosts.[ch] to common
 - initialize elanhost_config on demand in qsw.c
 - remove calls to elanhosts in slurmd/elan_interconnect.c
 - merge libhostlist into libcommon since elanhosts needs it.

completion plugin.