webpack-dev-server does not rebuild code example

Example: clean-webpack-plugin webpack-dev-server issue

webpack dev server causing the recompile and thus invocation 
of clean webpack plugin, which clears dist folder. but to keep files
there in dist folder you must instruct it to write to disk.

then after every recompile it writes files to disk this can be set
through writeToDisk:true,

devServer: {
index: 'index.html',
contentBase: path.join(__dirname, 'dist'),
compress: true,
hot: true, //Hot module replacement
port: 9000,
writeToDisk:true,
open: 'chrome' //open in chrome
}