Refactor

Fix username/mention regexes

* Allow underscore instead of hypen
* Fix domain part handling
* Add tests for remote mention

Update gulp-pug to the latest version 🚀

Fix banner selection from user page and drives

Previously, updateBanner takes a callback as a first argument of the function, but some calls passes a file object.

I've refactored it with Promise to avoid those misuses (although it should have type definitions :/)