[ADF-4152] Updated folder structure of core docs (#4415)

* [ADF-4152] Moved core library docs into subfolders

* [ADF-4152] Moved core library docs into subfolders

* [ADF-4152] Manual fixes to core doc file links

* [ADF-4152] Further automatic + manual link tidying

docs/core/components/language-menu.component.md

@@ -0,0 +1,78 @@
+---
+Title: Language Menu component
+Added: v2.0.0
+Status: Active
+Last reviewed: 2018-11-09
+---
+
+# [Language Menu component](../../../lib/core/language-menu/language-menu.component.ts "Defined in language-menu.component.ts")
+
+Displays all the languages that are present in "app.config.json" and the default (EN).
+
+![Language Menu screenshot](../../docassets/images/languages-menu.png)
+
+## Basic usage
+
+How to attach an ADF Language Menu as a main menu
+
+```html
+<button mat-icon-button [matMenuTriggerFor]="langMenu">
+    <mat-icon>language</mat-icon>
+</button>
+<mat-menu #langMenu="matMenu">
+    <adf-language-menu></adf-language-menu>
+</mat-menu>
+```
+
+## Details
+
+Add a [Language Menu component](language-menu.component.md) to let the
+user set the locale language for the app. For further information about the
+locale language, see the
+[Internationalization](../../user-guide/internationalization.md#how-the-display-language-is-selected)
+page in the user guide.
+
+The component fetches the list of available languages from `app.config.json`:
+
+```json
+"languages": [
+        {
+            "key": "en",
+            "label": "English"
+        },
+        {
+            "key": "fr",
+            "label": "French"
+        },
+        {
+            "key": "it",
+            "label": "Italian"
+        }
+    ]
+```
+
+If no `languages` setting is provided, the component shows only the English language.
+
+### Nested Menu language
+
+You can also attach the Language Menu as a nested menu:
+
+```html
+<button mat-icon-button class="dw-profile-menu" [matMenuTriggerFor]="profileMenu">
+    <mat-icon>more_vert</mat-icon>
+</button>
+<mat-menu #profileMenu="matMenu">
+    <button mat-menu-item>profile-settings</button>
+    <button mat-menu-item [matMenuTriggerFor]="langMenu">Languages</button>
+    <button mat-menu-item>sign-out</button>
+</mat-menu>
+<mat-menu #langMenu="matMenu">
+    <adf-language-menu></adf-language-menu>
+</mat-menu>
+```
+
+![Nested Language Menu screenshot](../../docassets/images/languages-menu-nested.png)
+
+## See Also
+
+-   [Internationalization](../../user-guide/internationalization.md)