Revert "zh-cn: Sync with upstream to keep it up-to-date (#374)" (#391)

This reverts commit 301b9d88.

#374 overwrote the English version of the solutions

README-zh-Hans.md

 > * 原文地址：[github.com/donnemartin/system-design-primer](https://github.com/donnemartin/system-design-primer)
 > * 译文出自：[掘金翻译计划](https://github.com/xitu/gold-miner)
-> * 译者：[XatMassacrE](https://github.com/XatMassacrE)、[L9m](https://github.com/L9m)、[Airmacho](https://github.com/Airmacho)、[xiaoyusilen](https://github.com/xiaoyusilen)、[jifaxu](https://github.com/jifaxu)、[根号三](https://github.com/sqrthree)
+> * 译者：[XatMassacrE](https://github.com/XatMassacrE)、[L9m](https://github.com/L9m)、[Airmacho](https://github.com/Airmacho)、[xiaoyusilen](https://github.com/xiaoyusilen)、[jifaxu](https://github.com/jifaxu)
 > * 这个 [链接](https://github.com/xitu/system-design-primer/compare/master...donnemartin:master) 用来查看本翻译与英文版是否有差别（如果你没有看到 README.md 发生变化，那就意味着这份翻译文档是最新的）。
 
 *[English](README.md) ∙ [日本語](README-ja.md) ∙ [简体中文](README-zh-Hans.md) ∙ [繁體中文](README-zh-TW.md) | [العَرَبِيَّة‎](https://github.com/donnemartin/system-design-primer/issues/170) ∙ [বাংলা](https://github.com/donnemartin/system-design-primer/issues/220) ∙ [Português do Brasil](https://github.com/donnemartin/system-design-primer/issues/40) ∙ [Deutsch](https://github.com/donnemartin/system-design-primer/issues/186) ∙ [ελληνικά](https://github.com/donnemartin/system-design-primer/issues/130) ∙ [עברית](https://github.com/donnemartin/system-design-primer/issues/272) ∙ [Italiano](https://github.com/donnemartin/system-design-primer/issues/104) ∙ [韓國語](https://github.com/donnemartin/system-design-primer/issues/102) ∙ [فارسی](https://github.com/donnemartin/system-design-primer/issues/110) ∙ [Polski](https://github.com/donnemartin/system-design-primer/issues/68) ∙ [русский язык](https://github.com/donnemartin/system-design-primer/issues/87) ∙ [Español](https://github.com/donnemartin/system-design-primer/issues/136) ∙ [ภาษาไทย](https://github.com/donnemartin/system-design-primer/issues/187) ∙ [Türkçe](https://github.com/donnemartin/system-design-primer/issues/39) ∙ [tiếng Việt](https://github.com/donnemartin/system-design-primer/issues/127) ∙ [Français](https://github.com/donnemartin/system-design-primer/issues/250) | [Add Translation](https://github.com/donnemartin/system-design-primer/issues/28)*
@@ -12,6 +12,14 @@
   <br/>
 </p>
 
+## 翻译
+
+有兴趣参与[翻译](https://github.com/donnemartin/system-design-primer/issues/28)?  以下是正在进行中的翻译:
+
+* [巴西葡萄牙语](https://github.com/donnemartin/system-design-primer/issues/40)
+* [简体中文](https://github.com/donnemartin/system-design-primer/issues/38)
+* [土耳其语](https://github.com/donnemartin/system-design-primer/issues/39)
+
 ## 目的
 
 > 学习如何设计大型系统。
@@ -83,7 +91,6 @@
 * 修复错误
 * 完善章节
 * 添加章节
-* [帮助翻译](https://github.com/donnemartin/system-design-primer/issues/28)
 
 一些还需要完善的内容放在了[正在完善中](#正在完善中)。