Add role to install nfs-server, cleanup roles and configuration

- use generic media_dirs including vdr recdir, loop over them to
  create directories, configure samba, nfs, etc.
- add role to install an configure nfs-kernel-server
- cleanup roles
- add custom fact modules

roles/grub-config/tasks/main.yml

@@ -11,6 +11,6 @@
       dest: /etc/default/grub
       state: present
       regexp: '^(GRUB_CMDLINE_LINUX_DEFAULT=")'
-      line: '\1{{ system.grub.boot_options}}"'
+      line: '\1{{ grub.boot_options}}"'
       backrefs: yes
   notify: [ 'Update GRUB' ]