Remove __future__ print_function

It turns out I'm using Python-3-specific features elsewhere in the code,
so there's no reason to continue partially trying to support Python 2.

kaylee.py

 # Copyright 2015-2016 Clayton G. Hobbs
 # Portions Copyright 2013 Jezra
 
-from __future__ import print_function
 import sys
 import signal
 import os.path