Add OPT_BOOL environment variable type to handle yes/no 1/0 boolean
type environment variables.

the error message from GNU sleep.

when the stdout is closed.

Also add extra check to prevent the slurmstepd from sending the IO EOF
msg twice for the same object.

parallel debugger.

fixes for BLUEGENE systems to run correctly with the new launching system with no addresses.  Also took node_addr out of slurm_step_layout_t

    better performance.