Add url for brand main page.

[gertlind]

Add url to :
data/brands/

Example:

uuid: ae5ff34e-298e-50c9-8f77-92a97fb30b09
slug: prusament
name: Prusament
url: https://www.prusa3d.com
countries_of_origin:
- CZ

[cristinarz98]

Thanks for the suggestion, it's a good idea :)