Handles spaces in array names better.

1/ When printing the "name=" entry for --brief output,
   enclose name in quotes if it contains spaces etc.
   Quotes are already supported for reading mdadm.conf

2/ When a name is used as a device name, translate spaces
   and tabs to '_', as well as the current translation of
   '/' to '-'.

Signed-off-by: NeilBrown <neilb@suse.de>