Rename scene lists
This takes the word "setup" out of various scene lists. Also took the opportunity to add "entry" to actor entry lists, and clean up some differences relating to spawn/entrances.
Relevant discord conversation: https://discord.com/channels/688807550715560050/838852326231769089/1003988882347544609
I still feel that exitList should be reconsidered-- the term "exit", to me, implies that an exit is its own seperate entity, when in reality this is just an entrance index. See discord conversation for details and opinions.
This pr is focused on the list names in play, not so much on the code in z_scene. A dedicated pass to clean things up in there, and changes to the command names/zapd output would be good to do asap.
reviving this PR now that elf_message has been taken care of. addressed most comments