Introduce a processor generator

What does this MR do and why?

I was going to add a new processor but I thought, it's a bit tedious and could be automated, so I quickly implemented this generator (which is purposely naive and in a single file for simplicity/boringness/iteration sake).

Expected impact & dry-runs

This should lower the barrier to implement a new processor.

Action items

• (If applicable) Add documentation to the handbook pages for Triage Operations =>
• (If applicable) Identify the affected groups and how to communicate to them:
  • /cc @person_or_group =>
  • Relevant Slack channels =>
  • Engineering week-in-review