added --enable-bluegene-emulation mode and fixed it so sview won't build on systems that don't have gtk installed.

removed task dist from srun put into slurmctld.  need to remove the addresses from job allocation since that isn't needed anymore.  need to fix some issues with the way sbcast does things now which should be easy.  The switch plugins can change also since we have the tasks laid out already now before we set up the switch.  Some more clean up also will be nice in srun.