Brand guideline page

[ThatsMrTalbot]

It may be useful to have a brand guideline covering some common topics:

• How to write cert-manager
• Allowed uses of the name/logo (I would link off to the official linux foundation page for this)
• Document cert-manager cert-manager colour palette
• Provide the cert-manager logo in a few different sizes

We could base some content on the CNCF brand guideline page

[ThatsMrTalbot]

/priority backlog