Update ProgramDesign

ProgramDesign.md

@@ -33,6 +33,7 @@ If you have twenty or thirty sprites, you will probably want to take the time to
 You should create a function to change the game mode.  We will place a call for this in a moment, but for now, we do something like: 
 
 * Clear all sprites:  The sprite controller has a process for returning all sprites that are duplicates of named sprites.  We can use that to clear all the sprites like:
+
 ```c#
 void ClearAllSprites()
 {