Summary:
This PR refactors the symlink finding logic in local-cli in order to support nested symlinked modules as well as symlinked scoped NPM modules.
Run tests, or try project with `npm link`'ed or `yarn link`'ed dependencies.
Closes https://github.com/facebook/react-native/pull/15776
Reviewed By: cpojer
Differential Revision: D5823008
Pulled By: jeanlauliac
fbshipit-source-id: f2daeceef37bed2f8a136a0a5918730f9832884c
Adam Miskiewicz