add zh_cn translation

[tristankechlo]

First of all, thanks for taking the time translating the mod!

Now I got a few points:

• If you want to be credited, also add your name to the Translations part of the Readme.md
• Are you ok with me, bringing the translation to newer modversions?

[HfSrJun]

First of all, thanks for taking the time translating the mod!

Now I got a few points:

• If you want to be credited, also add your name to the Translations part of the Readme.md
• Are you ok with me, bringing the translation to newer modversions?

feel free to use the translation in any other versions and if anything is changed or the translation has mistakes, I will edit to correct it

[tristankechlo]

Thank you for the translation