Optional tag for "Anti-fraud/Cyber Security/Digital Fraud" entries

[philipp-classen]

Candidates for such a tag:

• biocatch
• forter
• google_recaptcha
• distil_tag
• iovation
• trustlogo
• report_uri

Currently, we put these entries under "essential" category; but in doing so we lose the information that they are a subcategory of their own.

[philipp-classen]

This is loosely related to the essential cleanup: https://github.com/ghostery/trackerdb/issues/361