Transform CSS

[aalin]

• Support for composes (within the same file), https://github.com/css-modules/css-modules#composition (partially fixed in 20caf85)
• css: Create classes for tag-selectors and apply them automatically #25
• Extract external resources from @import statements for preconnect/prefetch hinting.
• Parse url() and create resources from images. Handle url() in CSS files #59
• CSS ordering causing cascade issues #38
• Look into calling Rust from Ruby (https://github.com/matsadler/magnus looks interesting) so we can use lightingcss Use lightningcss #54