Branch b1_4_mountconf

Branch b1_4_mountconf
b=9861
make mgsnids and failover nids part of string parameters
(e.g. mgsnode=<nid_list>), to simplify mkfs/mount, and to provide a
distinction between multiple nids per node, and multiple nodes.  String
parsing moves into kernel.  Arbitrary params can be added to mkfs.lustre
with --param key=value, hopefully preventing any need to ever change the
lustre_disk_data.