Improve deployment instructions

Author: janheinrichmerker

helm/targer/README.md

@@ -2,19 +2,27 @@
 
 Helm chart for installing Targer on a Kubernetes cluster.
 
+In the following commands `NAME` is the release name. That name is used for naming Pods, Volumes etc. A Kubernetes namespace may be configured in `NAMESPACE`. Skip the `-n NAMESPACE` option to deploy to the default namespace.
+
 ## Deployment
 
 1. Install [Helm](https://helm.sh/docs/intro/quickstart/) and configure `kubectl` for your cluster.
 2. Generate Kubernetes templates for manual error checking:
 
     ```shell script
-    helm template targer targer 
+    helm -n NAMESPACE template NAME targer 
     ```
 
     This step can be skipped, but the generated template gives you a good preview what will be deployed in the next step.
 3. Deploy to Kubernetes cluster:
 
     ```shell script
-    helm install targer targer 
+    helm -n NAMESPACE install NAME targer 
+    ```
+
+4. If you have previously deployed TARGER to your Kubernetes cluster, you can upgrade the release:
+
+    ```shell script
+    helm -n NAMESPACE upgrade NAME targer 
     ```