CBLT-254:  supply credentials to curl to upload artifacts to maven repo

Change-Id: Ib35d23cd5d0c36246feb60d94aeba344aa86baf2
Reviewed-on: http://review.couchbase.org/35557
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>