Syntax error when running app

[gdangelo]

Hi @samuxyz,

I obtain the following error when running the app:

> [email protected] start /Users/gdangelo/Desktop/instastack
> webpack-dev-server

/Users/gdangelo/Desktop/instastack/webpack.config.js:33
let config;
^^^

SyntaxError: Block-scoped declarations (let, const, function, class) not yet supported outside strict mode
    at exports.runInThisContext (vm.js:53:16)
    at Module._compile (module.js:387:25)
    at Object.Module._extensions..js (module.js:422:10)
    at Module.load (module.js:357:32)
    at Function.Module._load (module.js:314:12)
    at Module.require (module.js:367:17)
    at require (internal/module.js:16:19)
    at module.exports (/Users/gdangelo/Desktop/instastack/node_modules/webpack/bin/convert-argv.js:80:13)
    at Object.<anonymous> (/Users/gdangelo/Desktop/instastack/node_modules/webpack-dev-server/bin/webpack-dev-server.js:68:48)
    at Module._compile (module.js:413:34)

I fix it by placing 'use strict' at the beginning of webpack.config.js file.