Windows: warning removal

Windows: warning removal

cast away size_t larger than afs_uint32 warnings

use variables with the proper signed vs unsigned state in order
to avoid signed vs unsigned comparison warnings

disable deprecated string function warnings

LICENSE MIT

Change-Id: I78a3786a0766979c8d83cc5dbd06f91e70b0ee47
Reviewed-on: http://gerrit.openafs.org/2074
Tested-by: Jeffrey Altman <jaltman@openafs.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>