Github user aperepel commented on the issue:
https://github.com/apache/nifi/pull/2477
@pvillard31 we were discussing a modular design for commands with dynamic
discovery/loading (e.g. via Java's ServiceLoader mechanism). This is to support
the idea that we should try to incorporate as much reference documentation as
possible into command's output, and only add doc pages focusing on the
workflow, typical use cases and best practices instead. My $.02---
