Support Cloudflare proxied records

Some Ingress domains might want the Cloudflare records to be proxied (in CF they're marked with the orange cloud), enabling Cloudflare to serve as a proxy to the Ingress.

Requirements:
- per-Ingress setting at minimum, but better on a per-host
- probably should be combined with a page-rule that sets settings such as respecting cache headers returned from the Ingress, etc.
