make editting mods for partition and node.  hitting return in a popup now finishes with an ok instead of you having to hit it with the mouse

when --multi-prog is in use.

The slurmstepd now parses the multi-prog file earlier and keeps track
of the individual argv array for each task.  Searching the PATH
environment variable is still done just before task exec() time so that
the search is done as the user and not as root.

Major enhancements to all multi-core code, bug fixes, performance improvements, etc.

VER### in header.

for multi-prog runs.

Basically works, but needs cleanup and optimization (especially on the
server side).

Also, [srun|slaunch]/multi_prog.c are clearly buggy.

ported as necessary to v1.2.

consistency between the commands.