Support for subdomains

[b0Stark]

Would be nice if zipline could support subdomains for serving content.
I.e.,
Images: https://{{image}}.domain.tld/xxxx
Links: https://{{short}}.domain.tld/xxxx | Or even a secondary domain: https://ex.tld/xxxx
API: https://{{api}}.domain.tld

Quite frankly, I wouldn't mind mixing the content either so any kind of resource would show up as:
https://domain.tld/xxxx

[diced]

Adding this would be pretty difficult with how Zipline works currently, and wouldn't really make sense as there isn't much of a use case for this.