You need Hexo to build generate the blog. Right now it runs on Hexo 3.0.1.
npm install
When installed, go to blog folder and run hexo server -i 127.0.0.1. Enjoy your blog on 127.0.0.1:4000.
If you push your post to branch with prefix posts/ (e.g. posts/graphite), your post will be rendered and displayed at http://development.cnblogtest.divshot.io (cn/steen). Of course if somebody else pushes to another post/* branch your stuff will be overwritten. Use it to verify that your post is OK, including attachments.