Document product integration for fixing policy violations (OPA Gatekeeper)

Details:

• Identifying policies that will deny admission into the cluster
• Tips on fixing policies
• What to do if an exception is required
• Validating OPA Gatekeeper works with package

NOTES:

• Use PodInfo as the example app in all instructions. We want someone following the documents from beginning to end able to add podinfo into Big Bang.
• Placeholders for docs will be created in this MR. Format is markdown.
• Any overlapping sections in the original package integration doc should be cleaned up with references to this doc. The original may be renamed to package-integration-supported.md.