Read basic-auth data from secret

[matthijswolters-rl]

Reads basic-auth data from secret. Does that by creating a kubernetes client based on the service account used by the pod and reading secrets in it's own namespace. For more info read the included docs.

To Test:

1. run a local kubernetes cluster and set KUBECONFIG to the correct kubeconfig
2. run make install in repo dir
3. run the local docker registry docker run -d -p 5000:5000 --name registry registry:2
4. build the image and push it

• docker build -t localhost:5000/controller:latest .
• docker push localhost:5000/controller:latest

5. add the secret imc-config and test-secret and the endpoint monitor (ask me for the commands)
6. run make deploy
7. edit the deployment in ingressmonitorcontroller-system to use the image localhost:5000/controller:latest
8. kill the pod so it pulls the most recent version