Add react-hot-loader

[manrueda]

Add react-hot-loader to this great project!

[ghost]

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[ghost]

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[gaearon]

Hi, thanks for PR!
I would be comfortable including it only after both HMR infrastructure and RHL itself are more stable.

[zikaari]

Maybe we should have an experimental branch/release similar to how chrome has experimental flags, because having something like that is a good way to have massive community involved in usage and development*, and thus amp up contributions (bug reports and PR's)

* of create-react-app and its core deps (RHL etc.)

[stevemao]

Hi @gaearon , is React-Hot-Loader stable enough to be added here now?