[CBIT-532]: Initial checkin for go-manifest and go-set-versions scripts.

Change-Id: I1b81a3f12f9011180aeab6eca0eb2bb425819c14
Reviewed-on: http://review.couchbase.org/34873
Reviewed-by: Eric Limare <eric.limare@couchbase.com>
Tested-by: Eric Limare <eric.limare@couchbase.com>