Default behaviour is to print a message notifying the user.  Also added
the -K/--kill-command option, which tells salloc to send a signal to the
user's command when a job-complete message arrives.

rather than slurm function).

older tests.

from the step context, and the assiciated allocation lookup rpc.

Creating a step context now requires only a single RPC to the controller.

add tests for slaunch --debug and --verbose options

use output of function default_partition, otherwise use the partition 
explicitly named in your globals.local file

response to job completion RPC.

communication itself) fails