move github pages and itch publishing pages to their own folder

- I feel like this makes the directory structure feel more understandable; pages and itch publishing are now under "publishing" instead of under "pygbag"

Author: saffron

wiki/README.md

@@ -119,8 +119,8 @@ If using pygame-zero (mostly untested), put `#!pgzrun` near the top of main.py.
 
 ## Publishing
 
-- [Github Pages](/wiki/pygbag/github.io/)
-- [Itch.io](/wiki/pygbag/itch.io/)
+- [Github Pages](/wiki/publishing/github.io/)
+- [Itch.io](/wiki/publishing/itch.io/)
 
 ## Demos