Filter debug reducer actions & state_changes

I'm working on a video streaming platform and I want to have an ability not only to choose which actions I can listen to with debug() higher-order reducer, but also to choose which actions I want to ignore (CGImage output or loaded timeline updates are not very representative for debugging most of the stuff for me). And I think it feels natural to have such an option, so here is a place anyone can discuss that functionality, future implementation and API. Maybe I'll introduce some PR later if pointfree.co won't implement it first :slightly_smiling_face:.