Make file automatically if it does not exist

Remove readline import (this is Tk, we don't need console)
Remove coding line (we don't use any UTF-8 characters)
Add appdirs (find application data folder on various OSes)
- Add appdirs import
Handle files as list
Replace "if not in, do stuff" with "if in, skip" for cleanliness
Change name from "add" to "f" (clearer)