Update client.zh_CN.yml

1,Add tag
2,Fix translation
Store base URI in Discourse.BaseUri and use it in all places where rootURL was previously used
fix some typos in cs translation
consistent behavior regarding file uploads
get regular trust level going, self heal inconsistent topic timings
Merge pull request #654 from ZogStriP/consistent-behavior-regarding-file-uploads

consistent behavior regarding file uploads
Merge pull request #653 from kubabrecka/cs_typos

fix some typos in cs translation
Merge pull request #647 from windyson2008/patch-1

Update client.zh_CN.yml
Merge pull request #637 from wojciechka/master

Putting rootURL in JavaScript using Discourse::base_uri and erb
trust ranges are 0-4, not 0-5 (moderators diff)
clarify language on enable_private_messages
copyedits on Site Content editor help
topic reply count resync for each new post
some minimal site settings diags
fix issue where days_visited was totally out of sync
fix my broken test
a method called "adding_user_record" is annoying me. 5 lines of code replaced with 2