Prior to this commit, NewConfig was setting up a new Config object and
filling it with a new kubeconfig object. The process for creating a
kubeconfig object has the potential to return an error. This commit
removes the creation of that object from NewConfig, delegating creation
of kubeconfig objects to more appropriate functions, such as LoadConfig.
Change-Id: I57a040f2e76bbc003eb82171f382e80425b37870
e48b436680