Const declarations present in generated code

[cozmo8691]

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• Operating System: Windows 8.1
• Node Version: v6.10.1
• NPM Version: 4.0.3
• webpack Version: 2.7.0
• webpack-dev-server Version: 2.9.1

• [x ] This is a bug
• This is a feature request
• This is a modification request

Code

barebones project here

Expected Behavior

When running webpack-dev-server code should be transpiled to run in older browsers.

Actual Behavior

When running webpack-dev-server the generated code contains 'const' declarations which are causing errors in older browsers e.g. Safari on Ipad Air.

For Bugs; How can we reproduce the behavior?

npm i
npm start

[shellscape]

@cozmo8691 please do try a search before creating a new issue. I just closed an issue with the same exact report 42 minutes ago: #1143

Closing as duplicate.