添加第二章节教程多版本API (kubernetes-sigs#20)

docs/book/src/multiversion-tutorial/tutorial.md

@@ -1,44 +1,36 @@
-# Tutorial: Multi-Version API
+# 教程：多版本 API
 
-Most projects start out with an alpha API that changes release to release.
-However, eventually, most projects will need to move to a more stable API.
-Once your API is stable though, you can't make breaking changes to it.
-That's where API versions come into play.
+大多数项目都是从一个 alpha API 开始的，这个 API 会随着发布版本的不同而变化。
+然后，最终，大多数项目将会转向更稳定的版本。一旦你的 API 足够的稳定，你就不能够对它做破坏性的修改。
+这就是 API 版本发挥作用的地方。
 
-Let's make some changes to the `CronJob` API spec and make sure all the
-different versions are supported by our CronJob project.
+让我们对 `CronJob` API spec 做一些改变，确保我们的 CronJob 项目支持所有不同的版本。
 
-If you haven't already, make sure you've gone through the base [CronJob
-Tutorial](/cronjob-tutorial/cronjob-tutorial.md).
+如果你还没有准备好，确保你已经阅读过了基础的 [CronJob 教程](/cronjob-tutorial/cronjob-tutorial.md)。
 
 <aside class="note">
 
-<h1>Following Along vs Jumping Ahead</h1>
+<h1>跟随 vs 跳跃</h1>
 
-Note that most of this tutorial is generated from literate Go files that
-form a runnable project, and live in the book source directory:
-[docs/book/src/multiversion-tutorial/testdata/project][tutorial-source].
+注意本教程的大部分内容是由形成一个可运行的项目的 literate Go 文件生成的，并且放在了本书的下面源目录下 [docs/book/src/multiversion-tutorial/testdata/project][tutorial-source]。
 
 [tutorial-source]: https://github.com/kubernetes-sigs/kubebuilder/tree/master/docs/book/src/multiversion-tutorial/testdata/project
 
 </aside>
 
 <aside class="note warning">
 
-<h1>Minimum Kubernetes Versions Incoming!</h1>
+<h1>最小 kubernetes 版本来了！</h1>
 
-CRD conversion support was introduced as an alpha feature in Kubernetes
-1.13 (which means it's not on by default, and needs to be enabled via
-a [feature gate][kube-feature-gates]), and became beta in Kubernetes 1.15
-(which means it's on by default).
+CRD 转换在 Kubernetes 1.13 版本（也就是说它是默认关闭的，需要通过一个 [feature gate][kube-feature-gates] 去打开）中作为一个 alpha 特性被引入支持，
+在 Kubernetes 1.15 版本（也就是说它是默认打开的）中变成了 beta 版。
 
-If you're on Kubernetes 1.13-1.14, make sure to enable the feature gate.
-If you're on Kubernetes 1.12 or below, you'll need a new cluster to use
-conversion. Check out the [KinD instructions](/reference/kind.md) for
-instructions on how to set up a all-in-one cluster.
+如果你的 Kubernetes 版本是 1.13-1.14，确保开启了特性开关。
+如果你的 Kubernetes 版本是 1.12 或者更低，你将需要一个新的集群去使用转换。
+查看 [Kind 说明](/reference/kind.md) 去了解如果设置一个多功能的集群。
 
 </aside>
 
-Next, let's figure out what changes we want to make...
+接下来，让我们弄清楚我们想要做哪些更改。..
 
 [kube-feature-gates]: https://kubernetes.io/docs/reference/command-line-tools-reference/feature-gates/ "Kubernetes Feature Gates"