add nfs-provisioner with sensible path template

infrastructure/nfs-provisioner/README.md

@@ -0,0 +1,20 @@
+## How to use
+This deployment exposes a `StorageClass` named `nfs-client` that can be used to create `PersistentVolumeClaim` resources:
+
+
+```
+kind: PersistentVolumeClaim
+apiVersion: v1
+metadata:
+  name: test-claim
+  namespace: test-namespace
+spec:
+  storageClassName: nfs-client
+  accessModes:
+    - ReadWriteMany
+  resources:
+    requests:
+      storage: 1Mi
+```
+
+This will create a new folder in the NFS server under `<base-path>/test-namespace/test-claim` and mount it.