[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/pipes/app-config.pipe.md

@@ -0,0 +1,45 @@
+---
+Title: App Config Pipe
+Added: v2.4.0
+Status: Active
+Last reviewed: 2018-05-24
+---
+
+# [App Config Pipe](../../../lib/core/app-config/app-config.pipe.ts "Defined in app-config.pipe.ts")
+
+Retrieves values from the application configuration file directly.
+
+## Basic usage
+
+```html
+<adf-login
+    copyrightText="{{ 'application.copyright' | adfAppConfig }}">
+</adf-login>
+```
+
+## Details
+
+### Fallback values
+
+You can use the pipe parameter to pass a fallback value which will be
+used if the property name is not found:
+
+```html
+<adf-login
+    copyrightText="{{ 'application.copyright' | adfAppConfig:'Fallback Text' }}">
+</adf-login>
+```
+
+### Chaining with other pipes
+
+You can also chain values with other pipes such as the translation pipe:
+
+```html
+<adf-login
+    copyrightText="{{ 'application.copyright' | adfAppConfig | translate }}">
+</adf-login>
+```
+
+## See also
+
+-   [App Config service](../services/app-config.service.md)