Add policy annotations to all GKE hardening related polices

[dekuhn]

Based on go/policy-bundles - the recommended annotations would look something like:
bundles.validator.forsetisecurity.org/[bundle_key]: [control]

Please add details for all GKE Hardening Policies
Example:
description: Disable the Kubernetes web UI (Dashboard)
bundles.validator.forsetisecurity.org/gke-hardening-guideline:

[dekuhn]

@joecheuk we might to define some method for the [control] value related to GKE hardening guidelines or leave it blank

[morgante]

@dekuhn I recommend not leaving the control value blank, but instead come up with a control name for each guideline. Ex.

bundles.validator.forsetisecurity.org/gke-hardening-guideline: DISABLE_WEB_UI

[dekuhn]

@morgante @ryanismert @blueandgold - FYI
@joecheuk lets move forward with the following annotation format for GKE Hardening Guidelines
bundles.validator.forsetisecurity.org/gke-hardening-v2019.11.11: DISABLE_DASHBOARD_UI

It will be up to the engineer when adding these annotations to determine the text control name e.g. DISABLE_DASHBOARD_UI for each GKE hardening guideline.

[dekuhn]

I spent a little time starting to update a few rules today.
#199
#200