Fixes #4597: `yii\composer\Installer::setPermission()` supports setting permission for both directories and files now (qiangxue)
Added automatic generating of unique slug value to `yii\behaviors\Sluggable`
Default event for `yii\behaviors\Sluggable` with `unique` enabled changed to 'insert'.
Fixes #4644: Added `\yii\db\Schema::createColumnSchema()` to be able to customize column schema used
Merge pull request #4679 from bevalorous/docs-guide-russian-translation

Docs guide russian translation: translated rest-routing.md into Russian
Fixes #4673
Fixes #4371: Active form client validation wasn't working in case of two models having same named fields

When rendering multiple models in the same ActiveForm if any of the field names in the two models is the same then the corresponding attribute in the yiiActiveForm object in yiiActiveForm.js (ie $('form').data('yiiActiveForm').attributes) of the first rendered model is overwritten by the attribute of the last model causing the client-side validation for the overwritten field not to run at all. Example: given two models Car and Owner with attributes {make, age} and {name, age} then if the Car is rendered first its age attribute will not have any client validation.
Added information about format of Data column
Created ArrayCache class

- can be used to enable caching in a request without the need for any storage
- useful for example in complex console tasks that should still be independed
Adjusted data column docs
Fixes #4122: `Html::error()` and `Html::errorSummary()` are now accepting `encode` option. If set to false it prevents encoding of error messages
BaseHtmlPurifier config can now be a closure

`$config` can now be a closure that will have the `$configInstance` passed as the first param.

updated docs.

close #4656
changelog for #4656
Added test that are making sure batchInsert boolean values in PostgreSQL isn't failing with errors

close #4655
fix issue with postgreSQL and batch inserting boolean values

fixes #4654
ensure postgres boolean values are handled correctly

also fixed an issue with default value loading of bool columns.

fixes #3489, fixes #4085, fixes #3920
related to #4672
Merge branch 'master' of git://github.com/yiisoft/yii2

Conflicts:
	framework/CHANGELOG.md
Use 0666 to set files as writable.
Fixes #4586: Signed bigint and unsigned int will be converted into integers when they are loaded from DB by AR
removed the key from the array in the fix for #4371