Fix a spelling error

lib/Accessory.js

@@ -501,7 +501,7 @@ Accessory.prototype.publish = function(info, allowInsecureRequest) {
  * Accessory object will no longer vaild after invoking this method
  * Trying to invoke publish() on the object will result undefined behavior
  */
-Accessory.prototype.destory = function() {
+Accessory.prototype.destroy = function() {
   this._server.stop();
   this._advertiser.stopAdvertising();