SSL Customer Cert Upload

Allow CDN tenants to upload a custom cert to the CDN for application to their services.

Customers that split traffic across multiple CDNs have to use their own FQDN and SSL cert. We need a process for them to securely upload their certs to us for storage and application against their services.

We also need to capture the FQDN of the cert and make sure it is applied as a host regex for their service so that the CDN recognizes it. It's possible that it is already in place when they upload the cert, but this should be checked.