Babel 6

[emmenko]

Things to note for the upgrade:

• upgrade .babelrc as per babel 6 requirements
  • the order of presets seems to be important, especially the stage-0
  • default export interop changed, so if you require the module using commonjs you need to explicitly define .default (e.g.: require('./foo').default) https://phabricator.babeljs.io/T2212#57729
• don't use annotations for decorators (not supported in babel 6 yet), just use function composition instead
• ensure static properties have a semicolon babylon: throw parse error if class properties do not have a semico… babel/babel#3225
• babel-plugin-react-intl seems to have a bug if enforceDescriptions: true Description strangely missing using babel 6 formatjs/babel-plugin-react-intl#26

[mattdell]

@emmenko did your app.min.js file increase or decrease after this?

Mine seems to have increased by 140kb and I was hoping this upgrade would result in a smaller file size.