Public Path Prefix

[daniel-centore]

Description

Adds the ability to customize the public path of AWS files using a custom prefix instead of pulling from the AWS library

Motivation and context

This makes it possible to use a CDN (like Cloudflare) in-between AWS (or compatible) and the user

How has this been tested?

• Created Backblaze B2 bucket and configured to work with my Omeka S instance without using this new feature
• Confirmed I can access file attachments and that the URLs are of the form https://bucketname.s3.region.backblazeb2.com/...
• Followed instructions at https://www.backblaze.com/blog/free-image-hosting-with-cloudflare-transform-rules-and-backblaze-b2/ to configure to configure Backblaze+Cloudflare
• Added a Public Path Prefix of the form https://cdn.mydomain.com/file/bucketname to the AnyCloud settings
• Confirmed I can still access file attachments and that the URLs are of the form https://cdn.mydomain.com/file/bucketname/...

Screenshots (if appropriate)

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