Added breadcrumbs support

[vovsky]

Description

Added breadcrumbs support. Breadcrumb item includes the following fields: category id, name, level and URL key.

Fixed Issues (if relevant)

1. Add breadcrumbs support #19 Add breadcrumbs support

Manual testing scenarios

Sample query:

{
  category(id:5){
    name,
    breadcrumbs{
      category_id,
      category_name,
      category_level,
      category_url_key
    }
  }
}