Add the option "Access-Control-Allow-Origin" to the devServer config

[leogout]

Hi, I had to add headers: { 'Access-Control-Allow-Origin': '*' }, to the devServer section in webpack.config.js in order to get the hot reload to work.
This was the error message:

I found the solution on this issue: gaearon/react-hot-loader#56
My configuration:

• Brand new Symfony 3.2.8
• Running on 127.0.0.1:8000 (php bin/console server:start)
• Running php bin/console maba:webpack:dev-server

If this solution suits you, i can make a PR.

Thanks for your work, you are saving me a lot of time !

Cheers.

[m-albo]

+1 Thx @leogout for this fix!

[mariusbalcytis]

Thanks for the fix!

I've also found some related changes needed for newer webpack-dev-server in case it's ran on another host, added needed configuration parameters to readme.