delete 127.0.1.1 from /etc/hosts on ubuntu compute node

xCAT-server/share/xcat/install/scripts/post.ubuntu

@@ -188,6 +188,10 @@ elif [[ -r /boot/grub/grub.cfg ]] ; then
 update-grub
 fi
 sed -i 's/\(deb.*security.*\)/#\1/' /etc/apt/sources.list
+#iso does not contains source deb packages
+sed -i 's/^\(\s*deb-src.*install.*\)$/#\1/g' /etc/apt/sources.list
+#delete the 127.0.1.1 line from /etc/hosts
+sed -i '/127.0.1.1/d' /etc/hosts
 updateflag.awk $MASTER 3002
 cd /
 #rm -Rf /xcatpost