Add kratos container

Add Kratos container.

helmchart/single-sign-on/README.md

 Please refer to the [online documentation](.../helmchart)
 
 
-# apply PVC
-kubectl apply -f pvc.yaml -n oas
 
-# install
-helm upgrade -f ../current.yaml single-sign-on . --debug -n oas
+This helmchart provides a first iteration of kratos services
+as backend for user database storage. 
+
+The Kratos backend is not used by applications yet and is just
+added to provide an infrastructure to develop the new frontend.
+
+To apply this helmchart for testing and add kratos to your
+stackspin cluster for development, follow those steps. Please
+note, it can be needed to specify the right namesapce (`ex: -n oas`)
+
+1. Backup you cluster values:
+```
+helm get values single-sign-on > cluster-values.yaml
+```
+
+2. Upgrade the helm chart to include kratos
+
+```
+helm upgrade -f ../cluster-values.yaml single-sign-on . --debug
+```