[Feature] Exclude dependencies from bundle

[renanbatel]

Webpack has a externals option that provides a way of excluding dependencies from the bundle, it's useful when you use a library on development, but you don't want it on your bundle because it'll be available on the production environment.

There's this JQuery use case, but it'll be also useful if you plan to support Node, where some dependencies can be available in the runtime environment like we see on serverless platforms.

[evanw]

This is now possible with the --external flag. Pass --external:foo to exclude foo from the bundle.