Create-react-app: Enable webpack v2 performance hints

[Timer]

• [x] [Add lint rule to disallow require.ensure](https://github.com/facebookincubator/create-react-app/issues/1524) (https://github.com/facebookincubator/create-react-app/pull/1536)
• [x] [Add support for dynamic import()](https://github.com/facebookincubator/create-react-app/issues/1192) (#1538)

• [ ] Document dynamic import

• [ ] Tune performance hint thresholds

• [ ] https://github.com/webpack/webpack/issues/4292

[sokra]

btw. you can disable require.ensure in webpack 2.

module: {
  rules: [
    { parser: { requireEnsure: false } }
  ]
}

[Timer]

Neat, thanks @sokra!

[Timer]

We should probably watch https://github.com/webpack/webpack/issues/4292 (unrelated to this issue, but something to not forget about when cutting 0.10.0).

[gaearon]

Going to push this back to 0.11.

[Timer]

We've added our own performance hints about post-compression size, closing this as unnecessary.