Added support for building cbsasl statically with msvc.

Change-Id: Ib2dd4f58384c151177308d5424f6295e514b3bee
Reviewed-on: http://review.couchbase.org/29765
Reviewed-by: Mark Nunberg <mnunberg@haskalah.org>
Tested-by: Sergey Avseyev <sergey.avseyev@gmail.com>