npm link no longer works

Since we changed the build process in https://github.com/frig-js/frigging-examples/commit/878f7fe1168a276763422c0ae64f6b041f2d154d, (and https://github.com/frig-js/frigging-bootstrap/pull/51), using `npm link` to develop examples/frig/frigging-bootstrap "in place" no longer works.
