Update usage example in nodeconfig
Update usage example in nodeconfig

Provide a customized usage string to more accurately show
the structure of a nodeconfig command.

whowutwut/confluent,whowutwut/confluent,whowutwut/confluent,jjohnson42/confluent,xcat2/confluent,xcat2/confluent,whowutwut/confluent,jjohnson42/confluent,xcat2/confluent,xcat2/confluent,jjohnson42/confluent,xcat2/confluent,jjohnson42/confluent,jjohnson42/confluent