translate
translated.
translated.
Merge remote-tracking branch 'origin/master'

Conflicts:
	docs/guide-zh-CN/intro-yii.md
translated.
translating..
type validation adjusted
fixed tests
updated CHANGELOG line
translated
Merge branch 'master' of https://github.com/yiisoft/yii2
Merge pull request #3867 from riverlet/zh-CN-translate-0604

Chinese guide
Fix mantain the code in english for start-hello.md
Spanish translation of start-forms.md
Create db-active-record
Create db-dao.md

暂未校对
Merge pull request #3873 from SuperPuppet/patch-2

Create db-dao.md
Merge pull request #3872 from SuperPuppet/patch-1

Create db-active-record.md
undo changes
updated FileValidator , CHANGELOG.md , UPGRADE.md guides , tests fixed
fixed CHANGELOG notes