Adjusting docs and example

- Removed explicit setting of snapshot flags
- Removed node selector on replicaset to reduce manual steps for users

Signed-off-by: Justin Nauman <justin.r.nauman@gmail.com>

examples/nginx-app/with-pv.yaml

@@ -62,8 +62,6 @@ spec:
           - mountPath: "/var/log/nginx"
             name: nginx-logs
             readOnly: false
-      nodeSelector:
-        app: nginx
 
 ---
 apiVersion: v1