Add Node's path module

[hamzaOp]

Add Node's path module to the static-files example.

[blakeembrey]

Seems like a useful change for people that don't realise it's how you should be doing it. However, can you avoid unnecessary changes? Just make it path.join inline instead of using variables, and avoid the new additions. I'd also follow the existing code style, which is to have a space after the comma between arguments.

[hamzaOp]

Thanks for the feedback :) , actually this is my first contribution so I'm still learning how to improve the code properly.

[blakeembrey]

Awesome! It looks great now 😄

FWIW, you can also do path.join(__dirname, 'public/css'). Either way, I'm happy to merge this change!

[hamzaOp]

Thank you 😄

[bbodenmiller]

Shouldn't this also be updated at https://expressjs.com/en/starter/static-files.html (https://github.com/expressjs/expressjs.com/blob/gh-pages/en/starter/static-files.md)?

[dougwilson]

@bbodenmiller see expressjs/expressjs.com#719