Add basic webpack loaders e.g. url and css-loader

[swernerx]

What would be super helpful would be some kind of support for "importing" CSS files and externals files via standard es2015 import syntax like Webpack does.

Only thing needed here for a first step would be resolving urls (especially when merging files from different sub directory levels) and handling basic CSS modules where the file is copied and CSS module names are exported.

The rollup plugin system could be a great inspiration here.

[sgentile]

+1 to add: font support so a file loader as well ?