Add proof, testing, and supporting code

testing.py

@@ -0,0 +1,33 @@
+# testing.py
+# By Chris Proctor
+#
+# Tests one letter in `typeface`. This testing script will be very useful
+# as you work on one letter at a time. If you want to change which letter
+# is tested, edit line 31 below. 
+# 
+
+from turtle import *
+from grid import draw_grid
+from superturtle.movement import no_delay
+import typeface
+
+UNIT = 40
+GRID_COLOR = "lightgrey"
+GRID_SIZE = 1
+LETTER_COLOR = "black"
+LETTER_SIZE = 3
+
+penup()
+goto(-160, -160)
+pendown()
+
+with no_delay():
+    color(GRID_COLOR)
+    pensize(GRID_SIZE)
+    draw_grid(UNIT)
+
+color(LETTER_COLOR)
+pensize(LETTER_SIZE)
+typeface.draw_letter_a(UNIT)
+
+input()