Make 'fs listquota' output readable for large quota

Make 'fs listquota' output readable for large quota

With the old print format quota and used values became one large
number for quotas in the terabyte range.

Fix alignment of the "no limit" string in the Windows fs command
for volumes with no quota.

Reviewed-on: http://gerrit.openafs.org/34
Verified-by: Russ Allbery <rra@stanford.edu>
Reviewed-by: Russ Allbery <rra@stanford.edu>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>