Revert "Fixes #3760: Gii model generator now imports classes when necessary instead of using fully qualified class names"

This reverts commit 0c8faedd.

Docs ja 2014 10 23

[ci skip] Update yii.php

Typo fix [ci skip]

Fixes #3760: Gii model generator now imports classes when necessary instead of using fully qualified class names

[skip ci] Lost link

[ci skip] docs/guide-ja/start-hello.md added

Fixes #5682: The `asset` command would incorrectly combine CSS files when `UrlManager::linkAssets` is true

Fixes #5570: `yii\bootstrap\Tabs` would throw an exception if `content` is not set for one of its `items`
Fixes #5572.

doc fix [skip ci]

Replaced single quotes in comment