Adding new NHC for xorg.conf so that vglrun works on vis nodes

roles/nhc/files/scripts/check_xorg_conf_file_existance.nhc

+#!/bin/bash
+
+function check_xorg_conf_file_existance() {
+#echo ">>> Checking xorg.conf File Existance >>>>>>>>>>>>>>>>>>>>>>>>>"
+
+test -e /etc/X11/xorg.conf
+
+if [ $? -ne 0 ]
+then
+     die 1 " $FUNCNAME ERROR xorg.conf File Not Detected"
+     return 1
+fi
+return 0
+}