lib/queue.js
function() {
          var next;
          running.pop();
          if (queue.length > 0 && running.length < limit) {
            switch (type) {
              case "lifo":
                next = queue.pop();
                break;
              default:
                next = queue.shift();
            }
            running.push(next);
            return next.resolve();
          }
        }
function() {
          var next;
          running.pop();
          if (queue.length > 0 && running.length < limit) {
            switch (type) {
              case "lifo":
                next = queue.pop();
                break;
              default:
                next = queue.shift();
            }
            running.push(next);
            return next.resolve();
          }
        }
Signals the queue an item is done running

@function ready

@return None