doc: link to code of conduct and contribution page

.github/CODE_OF_CONDUCT(zh_CN).md

@@ -1,3 +1,5 @@
-# 行为准则
+[English](CODE_OF_CONDUCT.md) | 中文
 
-// 该页面待补全, 关于通用的行为准则请参见 [Arch 的行为准则](https://wiki.archlinux.org/index.php/Code_of_conduct_(简体中文)) 页面. 
+## 行为准则
+
+参与所有 Deepin 项目均需您遵守 [Contributor Covenant 1.2 贡献者行为准则](https://www.contributor-covenant.org/version/1/2/0/code-of-conduct.html)。如果您对此有疑问，请邮件咨询 [email protected] 。

.github/CODE_OF_CONDUCT.md

@@ -1,3 +1,5 @@
-# Code of conduct
+English | [中文](CODE_OF_CONDUCT(zh_CN).md)
 
-// This is a working-in-progress page, for generic rule please consider refer to [Arch Code of Conduct](https://wiki.archlinux.org/index.php/Code_of_conduct).
+## Code of conduct
+
+All Deepin projects adheres to the [Contributor Covenant 1.2](https://www.contributor-covenant.org/version/1/2/0/code-of-conduct.html). By participating, you are expected to uphold this code. Please report unacceptable behavior to [email protected].

.github/CONTRIBUTING(zh_CN).md

@@ -0,0 +1,3 @@
+[English](CONTRIBUTING.md) | 中文
+
+请参阅 [开发者代码贡献指南](https://github.com/linuxdeepin/developer-center/wiki/Contribution-Guidelines-for-Developers) Wiki 页面。

.github/CONTRIBUTING.md

@@ -0,0 +1,3 @@
+English | [中文](CONTRIBUTING(zh_CN).md)
+
+Please refer to [Contribution Guidelines for Developers](https://github.com/linuxdeepin/developer-center/wiki/Contribution-Guidelines-for-Developers-en) from the wiki page.