Allow sub-directories within theme folders for better file organization.

[davidmurdoch]

We can "fake" sub directories by replacing the "/" (forward slash) character with a magic string, like "DIR" (Shopify doesn't allow special characters in filenames, otherwise I'd just use a solidus /), i.e., the resource assets/css/main.css would be referenced and uploaded as assets__DIR__css__DIR__main.css (or something).

[timdmackey]

Interesting idea! One thing I find frustrating about Shopify theme development is the single monolithic assets folder.