address (Hongjia Cao, National University of Defense Technology).

since those versions of MPI specify the LAM MPI plugin on the srun execute line.

Modify set_span function to take an optional desired fanout parameter.

fail after an "scontrol reconfigure".

Make slurm_addr slurm_conf_get_addr return an integer return code.

Remove unused variables in read_config.c.

requires that all source files be rebuilt if sysconfdir or pkglibdir
changes. 

Instead, src/common/Makefile now generates global_defaults.c, which 
contains global symbols "default_plugin_path" and "default_slurm_config_file"
which means that only this source file needs to be rebuilt, and
libcommon relinked when sysconfdir or pkglibdir are redefined.

Important bug fixed to increase default data block size.