Backup the non-default Rack Awareness Topology script

Backup any custom configurations of the rack awareness topology script.

In the Ambari HDFS service, if net.topology.script.file.name is configured with a non default topology script (that is not the default /etc/hadoop/conf/topology_script.py script), then take a backup of it.

After transitioning to Cloudera Manager, you can reconfigure your script.