test shrinko-8 code minification

[icegoat9]

To potentially save compressed size (and characters, though that matters less), try out newer PICO8 minifiers such as https://github.com/thisismypassport/shrinko8 . Mostly relevant thinking ahead to a PICOhaven "chapter 2"

[icegoat9]

Tried basic minification and got it to work well with --preserve "." (avoid renaming table keys), will likely include that.

Could test further optimization by calling out specific table keys to preserve (changestate(tablekey) for example)

Could also test the .png export via shrinko8