Enh: Name of webpack config should default to `webpack.config.js`

[TheLarkInn]

What is the current behavior?
I noticed that in the default setup, that a "webpack.dev.js" file was created. By default webpack looks for webpack.config.js at the root of a project. For the sake of cleanliness and easy to write scripts, we should be outputting webpack.config.js as the default. For dev and prod versions (I'll put in a separate issue for this).

Please paste the results of webpack-cli info here, and mention other relevant information
Versions

"dependencies": {
    "webpack-cli": "^3.1.2"
  },
"devDependencies": {
    "@webpack-cli/init": "^0.1.2",
}

[evenstensberg]

Will have a look!