Write ACL/RBAC docs

Author: Jurian Sluiman

docs/4.Authorization.md

@@ -1,14 +1,19 @@
 # Authorization
+ZfcAdmin allows authorization via [BjyAuthorize](https://github.com/bjyoungblood/BjyAuthorize) or [ZfcRbac](https://github.com/ZF-Commons/ZfcRbac). Configuration for both modules is provided to easily configure ZfcAdmin. Authorization enables you to restrict access to `/admin` and every other page under ZfcAdmin.
 
-Restrict access to unauthorized Users.
+## BjyAuthorize authorization
+BjyAuthorize works with `Zend\Permission\Acl` as access restriction component. The BjyAuthorize module combines `Zend\Permission\Acl` with the standard user module [ZfcUser](https://github/com/ZF-Commons/ZfcUser). To enable access restriction with BjyAuthorize, install the module and enable it in your `application.config.php`.
 
-### Solution
+Furthermore, ZfcAdmin has a `zfcadmin.global.php` file in the [config](../config/) directory. Copy this file over to your `config/autoload` directory. It directly provides BjyAuthorize configuration to restrict access to users for the `/admin` route. Only users in the "admin" group are allowed to access ZfcAdmin's pages.
 
-1. Install BjyAuthorize and enable in you application.config.php
-2. Import data/data.sql into your database.
-3. Create a user with ZfcUser and set the user_id and role_id in the database
-    (e.g. user_id = 1, role_id = admin)
+Instructions for further configuration of BjyAuthorize are provided in the [repository of BjyAuthorize](https://github.com/bjyoungblood/BjyAuthorize).
 
+## ZfcRbac authorization
+ZfcRbac works with `Zend\Permission\Rbac` as access restriction component. The ZfcRbac module combines `Zend\Permission\Rbac` with the standard user module [ZfcUser](https://github/com/ZF-Commons/ZfcUser). To enable access restriction with ZfcRbac, install the module and enable it in your `application.config.php`.
+
+Furthermore, ZfcAdmin has a `zfcadmin.global.php` file in the [config](../config/) directory. Copy this file over to your `config/autoload` directory. It directly provides ZfcRbac configuration to restrict access to users for the `/admin` route. Only users in the "admin" group are allowed to access ZfcAdmin's pages.
+
+Instructions for further configuration of ZfcRbac are provided in the [repository of ZfcRbac](https://github.com/ZF-Commons/ZfcRbac).
 
 ## Link to documentation pages