Modify the zh-cn page

[cherinyy]

We cannot view google.com in China, and other browsers have dedicated Chinese websites.

Chrome: https://www.google.cn/chrome Firefox: https://www.firefox.com.cn Opera: http://www.oupeng.com

[ghost]

• First, Firefox and Opera websites are not blocked in China.
• Secondly, www.firefox.com.cn provide install-package not same as www.firefox.com. People use www.firefox.com.cn can't log in Firefox Account! Please learn more about that.

[cherinyy]

time out