[ADF-2131] Search sorting (#3334)

* sorting configuration

* detect primary sorting and use with document list

* search results sorting

* docs update

* unit tests and code updates

* update code

* update code

* generic sorting picker, test updates

* ability to switch off client side sorting

* update docs for document list

docs/core/sorting-picker.component.md

@@ -0,0 +1,43 @@
+---
+Added: v2.4.0
+Status: Active
+---
+
+# Sorting Picker Component
+
+Provides an ability to pick one of the predefined sorting definitions and define sorting direction:
+
+```html
+<adf-sorting-picker
+    [options]="options"
+    [selected]="value"
+    [ascending]="ascending"
+    (change)="onChanged($event)">
+</adf-sorting-picker>
+```
+
+![Sorting Picker](../docassets/images/sorting-picker.png)
+
+## Options format
+
+You can bind a collection of any objects that expose the following properties:
+
+```ts
+{
+    key: string;
+    label: string;
+}
+```
+
+## Properties
+
+| Name | Type | Default Value | Description |
+| options | `Array<{key: string, label: string}>` | `[]` | Available sorting options. |
+| selected | `string` | | Currently selected option key. |
+| ascending | `boolean` | true | Current sorting direction. |
+
+## Events
+
+| Name | Type | Description |
+| --- | --- | --- |
+| change | `EventEmitter<{ key: string, ascending: boolean }>` | Raised each time sorting key or direction gets changed. |