[Suggestion] Disabling displaying JS Uglify Warnings

[marbor3]

There are quite some warnings while uglifying main.js file - most if not all from 3rd party libs.

Maybe it's a good idea to disable them by adding compress options:

new webpack.optimize.UglifyJsPlugin({
	mangle: {
		'keep_fnames': true
	},
	compress: {
		warnings: false
	}
})

[backflip]

https://github.com/unic/estatico-nou/ will introduce different log levels. As an example you can run the html task with different envs:

• $ NODE_DEBUG=estatico-handlebars npm run gulp html
• $ NODE_DEBUG=estatico-handlebars-extended npm run gulp html

However, I'm evaluating whether we can simplify this in https://github.com/unic/estatico-nou/issues/12