visualization.py
******************

This module handles all the visualization for any evolution.
The current implementation uses :mod:`pygame`

makeScreen(W, H)
================
Make an empty screen of width ``W`` and height ``H``

normalize(point, (olow, ohigh), (low, high))
============================================
This is a helper function. It takes a value for ``point``, originally measured in the scale [olow, ohigh].
The returned value is the corresponding value of ``point`` on the scale [low, high]

draw(tour, window, W, H, SCORES, COORDS)
=========================================
Draws a tour of a traveling salesman, and writes the score of the tour on the window.

Each city in the tour is represented as a red dot, with white lines connecting them.

``COORDS`` is a dictionary that contains the coordinates of the various cities.

The fitness score of ``tour`` is also written to ``window``

killscreen()
=============
This function cleans up pygame and destroys the window and the screen; to be called at the end of evolution.