Refactor fileio.py

Created by: sicklybeans

Currently fileio.py is a weird hybrid between config.py and classes.py

Part of it handles getting directories specific to the application.

Part of it handles reading/writing objects from files.

We should refactor it so that it's purpose is very clear. One way of doing this is to write a file whose only purpose is to write the objects in classes.py to strings which can be appended to arbitrary streams (this should perhaps go into classes.py itself).