better "kudurc" documentation

There is a possibility in Kudu to have cluster aliases to provide list of master addresses in a "kudurc" file, which is actually documented here:

https://kudu.apache.org/docs/administration.html#using_cluster_names_in_kudu_tool

This is a very useful feature if as I don't have to remember and/or type the list of master addresses every time I invoke a kudu CLU command. However, the above documentation is hard to find if you are not aware about the presence of this feature.

Maybe you could add a link to the Quickstart/Installation/Configuration guides to advertise, as it makes the administration from the cluster much easier if you know about this right in the beginning.