Docs: Update README with upgrade instructions

[blaisep]

I will add a few instructions on how to upgrade your OFC installation.

Expected Behaviour

After installation and customization, it's likely that the upstream version will change and it's not clear to the newcomer what steps they should take.

Current Behaviour

The current installation docs don't include any instructions for updating.

Possible Solution

Steps to Reproduce (for bugs)

1. Read https://github.com/openfaas/openfaas-cloud/tree/master/docs#openfaas-cloud-installation-guide
2. Note the absence of upgrade instructions.

Context

Your Environment

• FaaS-CLI version ( Full output from: faas-cli version ): CLI: (via home-brew OS X) commit: 5ff1504047756f9ff2e0a10ae64803ab63df470a version: 0.9.3

• Please also follow the troubleshooting guide and paste in any other diagnostic information you have:

[blaisep]

I can submit a PR summarizing @tmiklas instructions.

[blaise-sumo]

Does this look about right?

---

Update your installation

The versions are listed as tags in the repo: https://github.com/openfaas/openfaas-cloud/blob/$VERSION_TAG/stack.yml For example, the stack file for containing the image list for version 0.9.12 is at https://github.com/openfaas/openfaas-cloud/blob/0.9.12/stack.yml

You can check the versions of your running images:

kubectl get pods -n openfaas-fn -o jsonpath="{.items[*].spec.containers[*].image}"

Follow these instructions to pick up the latest updates from upstream:

Edit your configuration file: kubectl edit -n openfaas-fn deployment import-secrets and change the image version number to match the new values from the latest stack file.

[blaise-sumo]

...based on the discussion in the Slack channel, this ticket can be closed.

[Waterdrips]

/close ^