Added content to give a clear example to those that don't intuitively know how to set the template property using array notation.

close #6811

fixes #4602, close #4624

issue #2852

use toRoute() instead of createUrl() in ActionColumn

fixes #2276

The signature for `yii\gridview\ActionColumn::urlCreator` is changed - the `$action` parameter is moved to the first

Fixes #1499: Added `ActionColumn::controller` property to support customizing the controller for handling GridView actions

- added example code for application components
- added missing short description

[ci skip]

Related to b3b5e36d.

crud generator WIP.