* Make error overlay to run in the context of the iframe
* Configure webpack to build the entire package
* Remove inline raw-loader config
* Configure watch mode for error-overlay webpack build
* Add polyfills to the error-overlay iframe script
* Add header comment
* Configure to fail CI on error or warning
* Suppress flow-type error on importing iframe-bundle
* Change webpack to a dev dependency and pin some versions
* Disable webpack cache
* Update license headers to MIT
