Add get_points accessor

sugar/chat/sketchpad/Sketch.py

@@ -25,6 +25,9 @@ class Sketch:
 	def add_point(self, x, y):
 		self._points.append((x, y))
 
+	def get_points(self):
+		return self._points
+		
 	def draw(self, ctx):
 		start = True
 		for (x, y) in self._points: