Have ‘statistics’ and ‘marketing’ enabled by default

@sebastiaanvaz please note that having categories pre-checked for marketing is not GDPR compliant, and for statistics, it depends on your region and configuration. In that case Complianz will automatically pre-check the category.

However, if you have noted the above and still want this, we have created a small add on you can install:
https://github.com/Really-Simple-Plugins/complianz-gdpr-autocheck