Write instructions how to run controller locally #23

We need to write section in doc explaining how to run project in local Kind cluster.
currently blocked by #11

Steps to run projects:

• kind create cluster
• switch kubectl context to kind (important! otherwise you can damage production cluster)
• install cert-manager using helm or kustomize cert-manager documentation
• make docker-build to build docker image with tag controller:latest
• kind load docker-image controller:latest to load image into cluster
• make install (this installs CRD)
• make deploy (this deploys controller, roles, certificates)

After making changes in code to redeploy them run

• make docker-build, this will regenerate manifests and build image
• make deploy to change YAML manifests if necessary
• kubectl rollout restart -n etcd-operator-system deploy/etcd-operator-controller-manager