Small docs update suggestions

[stephen-last]

For paths, maybe add a couple more examples, including how to remove the contents of the folder, rather than the folder itself:

[
  'dist',      // removes 'dist' folder
  'build/*.*', // removes all files in 'build' folder
  'web/*.js'   // removes all JavaScript files in 'web' folder
]

For the root option, make it clear that it's the root of your package. The webpack.config file currently mentioned could actually sit anywhere, it doesn't have to sit in your package root folder (mine is in /webpack/index.js).

{
  root: __dirname // absolute path - your package root folder (paths appended to this)
}

I guess you could change webpack.config to package.json.

[johnagan]

done. thank you!