Pass in a kubernetes config location to load

[lholmquist]

This issue is for adding the ability to pass in a location for a configuration file. The kubernetes client that drives this library, has a loadFromFile method that can be used.
From the readme: https://github.com/godaddy/kubernetes-client#initializing

const { KubeConfig } = require('kubernetes-client')
const kubeconfig = new KubeConfig()
kubeconfig.loadFromFile('~/some/path')
const Request = require('kubernetes-client/backends/request')

const backend = new Request({ kubeconfig })
const client = new Client({ backend, version: '1.13' })

I think we can re-use the settings.config object that is already being passed in and make it multi-use. It can be an object, which it already is, or it can be a string, which would be a new config location and we can load that with the "loadFromFile" method