When.js 1.8.0 发布，Promises/A 的实现
When.js 1.8.0 发布了. When.js 是 cujojs 的轻量级的 Promises/A 和 when() 实现，从 wire.js 的异步核心和 cujojs 的 IOC 容器派生而来。包含很多其他有用的 Promiss 相关概念，例如联合多个 promiss、mapping 和减少 promises 集合以及 timed promises 等。
该版本改进内容：
- New when/function, when/node/function, and when/callbacks with functional programming goodness, and adapters for turning callback-based APIs into promise-based APIs. Kudos @riccieri!
- New when/unfold, and when/unfold/list promise-aware anamorphic unfolds that can be used to generate and/or process unbounded lists.
- New when/poll promise-based periodic polling and task execution. Kudos @scothis!
