Changed the `crossOriginLoading` option for webpack
Changed the `crossOriginLoading` option for webpack

With the react-router based webpack bundle splitting Webpack needs to
issue requests to fetch any bundles it needs to pull down. This changes
a setting for CORS options on that request, so as to ensure
compatibility with cloudfront.

mitodl/micromasters,mitodl/micromasters,mitodl/micromasters,mitodl/micromasters