This adds the optimization in CloudFlare where if a request is from the primary region then instead of redirecting to the CDN, we return the S3 URL to save egress cost
* cdn: add namespace and username to CDN redirect for usage calculation (PROJQUAY-5939)
We use the referer header to infer the namespace but that
is not always reliable as some clients don't add that header
when sending the request to the CDN
storage: Add Cloudflare as a CDN provider for an S3 backed storage (PROJQUAY-3699)
This adds CloudFlare as a CDN provider for quay for any storage backed
by S3. This requires a worker script that needs to be setup seperately
on CloudFlare. More details on the worker at
https://github.com/quay/quay-cloudflare-cdn-worker
