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

Added module class param to prevent error

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

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

Prevent 'Object configuration must be an array containing a "class" element.' error.

Fix faker test. Add `ё` to regexp

Fixes #5665: The `currentPage` meta data in the RESTful result should be 1-based, similar to that in HTTP headers

[ci skip] Translation in spanish and corrections

Use latest ES version for fix tests

#4471: `yii\caching\ApcCache` now returns array in case of APC is installed but not enabled in CLI mode

fixes #5652