MB-100: add couchbaselabs/cbsasl into manifest file

Change-Id: Ic05088c199f2bc8b3f78d06700f66c5694f8b0d9
Reviewed-on: http://review.couchbase.org/28279
Reviewed-by: Junyi Xie <junyi.couchbase@gmail.com>
Tested-by: Junyi Xie <junyi.couchbase@gmail.com>