neads cleanup

Simplified ArrayTrait::fields() default implementation since it works fine w/ just field names as values

New syntax:

```
[link to guide](guide:file-name.md)
[link to guide](guide:file-name.md#subsection)
```

fixes #4719

When an ID is found to be in both `Application::controllerMap` and `Application::modules`, the former will take precedence

Extracted inline action object creation, implemented it in console controller in order to use console inline action instead of base one

Fixes #4911: Changed callback signature used in `yii\base\ArrayableTrait::fields()` from `function ($field, $model) {` to `function ($model, $field) {`

`yii\base\ErrorHandler::handleError()` adjusted keeping native error processing on error reporting miss match.

Refactored `yii\web\User`.

Fixes #4519: `yii\base\Model::isAttributeRequired()` should check if the `when` option of the validator is set

fixes #4480

Security component adjustments: fixed comment style, hkdf() and pbkdf2() are now protected, compareString() is now public

Fixes #4409: Upper case letters in subdirectory prefixes of controller IDs were not properly handled