README: add GitPitch

README.md

@@ -114,6 +114,7 @@ There are 5 ways to install Gogs:
 - [Kanboard](http://kanboard.net/plugin/gogs-webhook) (Project Management)
 - [BearyChat](https://bearychat.com/) (Team Communication)
 - [HiWork](http://www.hiwork.cc/) (Team Communication)
+- [GitPitch](https://gitpitch.com/) (Markdown Presentations)
 
 ### Product Support
 

README_ZH.md

@@ -83,6 +83,7 @@ Gogs 的目标是打造一个最简单、最快速和最轻松的方式搭建自
 - [Kanboard](http://kanboard.net/plugin/gogs-webhook)（项目管理）
 - [BearyChat](https://bearychat.com/)（团队交流）
 - [HiWork](http://www.hiwork.cc/)（团队交流）
+- [GitPitch](https://gitpitch.com/)（Markdown 演示）
 
 ### 产品支持