Cartoon + monochrome shader (2nd attempt)

1. Addition of cartoon and monochrome shaders. Hopefully this time it merges properly.
2. Also added minor commit to new CRT shader per Boulotaur2024. Hope this shows up in the pull request, first time I've tried a new commit after creating the pull request.

Note: As I was adding the changes again I wondered if it matters what order the shaders are called in the stack and if they should maybe be re-ordered due to this?