Add Cloudflare Storage as Backup target

[robi]

To my pleasant surprise today I noticed a new service from CF called R2 (seems they're borrowing Backblaze naming of B2) which has an interesting free tier billed at GB-months.

Storage usage

Storage is billed using gigabyte-month (GB-month) as the billing metric. A GB-month is calculated by recording total bytes stored for the duration of the month.

For example:

• Storing 1 GB for 30 days will be charged as 1 GB-month.
• Storing 2 GB for 15 days will be charged as 1 GB-month.

More here:
https://developers.cloudflare.com/r2/platform/pricing/

[nebulon]

This appears to be S3 compliant, so I guess the generic S3 backend in Cloudron already would work?