The chief executive of a New Zealand adventure tourism company is flying to Nepal to support families of its contracted Sherpas after an avalanche on Mt Everest killed the porters. The bodies of 13 Sherpas had last night been recovered from an area between Base Camp and Camp 1. Three more Sherpas are believed to be buried under the snow and ice but couldn’t be found as bad weather closed in. Three of the Sherpas confirmed dead were contracted…