capture required bundles during server rendering

[goto-bus-stop]

so you can generate script tags for everything that is needed to render the page.

maybe having an api like splitRequire.capture(function (cb) { render(cb) }, function (result, bundles) {}) could be cool; could use the new async_hooks probably.

[diffcunha]

Not 100% related but you might want to take a look at this: https://github.com/nearform/choo-bundles