Fix random ResourceReader file loading

[RealSupremium]

You may not believe it (or you probably did already), but possible_names was actually a dictionary type before. The problem with that is you get these random numbers as keys, and the items inside go out of order.

[K0lb3]

It doesn't create a dict but a set. The idea behind it is to prevent duplicates, which used to be relevant before using .lowercase for the lookup. Now it's indeed not necessary to use a set anymore and a list would do, indeed.