Disable screen blanking by default via xorg configuration snippet

Further changes:
- add ppa:yavdr/experimental-kodi for KODI 18
- add set-kodi-display script to allow switching DISPLAY in dual
screen configuration (inkompatible with KODI 17)

roles/yavdr-xorg/tasks/detect-xorg.yml

@@ -174,3 +174,8 @@
     dest: /etc/X11/xorg.conf.d/20-intel.conf
   when:
     - intel_detected
+
+- name: server flags config snippet to disable screen blanking
+  template:
+    src: templates/10-serverflags.conf.j2
+    dest: /etc/X11/xorg.conf.d/10-serverflags.conf