Some codestyle fixes

AutoTimestamp field renaming

Feature fixture

Removing `abstract` in Module

Update Migration.php

add ability to use an array in multi columns parameters

Merge branch 'fixtures_except_option_added' of https://github.com/Ragazzo/yii2 into Ragazzo-fixtures_except_option_added

* 'fixtures_except_option_added' of https://github.com/Ragazzo/yii2:
  filter fix
  changelog added
  changes of other pr reverted
  except option added

Conflicts:
	framework/CHANGELOG.md

Corrected an error in the inline validator doc

Make HelpController check to make sure module controller path exists