This question is sort of an extension of what was brought up in this discussion: How to programmatically list all controllers in Rails
It seems most of the solutions for listing out an application's controllers and actions makes use of importing and parsing #{RAILS_ROOT}/app/controllers.
I've been building and making use of RoR Engines which are in #{RAILS_ROOT}/vendor/plugins/
How could these be included to list out every engine's controllers and actions?