Implement the custom role concept

- Custom Ansible roles can be stored in the `roles/custom` directory
- The list `custom_roles` determines which roles are included

lmn-client.yml

@@ -87,7 +87,6 @@
     - lmn_sssd
     - lmn_mount
     - lmn_kde
-    - lmn_fvs ## school specific customization
     - role: lmn_vm
       when: vm_support
     - lmn_printer
@@ -104,6 +103,14 @@
     - role: lmn_extrapkgs
 
   tasks:
+    - name: Include custom roles
+      ansible.builtin.include_role:
+        name: "custom/{{ rolename }}"
+      loop: "{{ custom_roles }}"
+      loop_control:
+        loop_var: rolename
+      when: custom_roles is defined
+
     ## Temporary fixes and quirks:
     - name: Remove disturbing NetworkManager connection
       ansible.builtin.file: