Adopt `allowlist` / `blocklist` terminology

[santiph]

This is my intent (choose one)

• [ ] I want to report a bug
• [x] I want to request a feature or change
• [ ] I want to provide or change a feature

The problem

Referring to something worth be blocked/excluded as Black, while adopted/included as White doesn't feel so right any more. Words Matter https://twitter.com/leahculver/status/1269109776983547904

Proposed solution

adopt more accurate terms as allowlist/blocklist to represent inclusion/exclusion