code: function() {
              if (_.size(this.tasks) > 0) {
                  this.empty = false;
                  var task = this.tasks.shift();
                  this.startTask(task);
                  this.trigger("tasks:next");
              } else {
                  this.empty = true;
                  this.trigger("tasks:finish");
              }      
          }
docs: /*
  Start next task