[2016] NZSC 115 JOHN EDWARD WHITEHEAD, ROSALENE MARIE WHITEHEAD AND EDWARD IVAN WHITEHEAD AS TRUSTEES OF THE J AND R WHITEHEAD TRUST v WATSON & SON LIMITED [2016] NZSC 115 [30 August 2016] IN THE SUPREME COURT OF NEW ZEALAND SC 65/2016 [2016] NZSC 115 B…