resolved scrolling issue (Issue 801) in filters list. it's a little verbose, but it seems to work. need to see if we can't refactor CheckUserInput to reduce the amount of code duplication. The logic for SimpleMenu is slightly different from the base method. perhaps we should override CheckUserInput to take in two parameters instead of one.

projects/mtg/include/SimpleMenu.h

@@ -40,6 +40,7 @@ public:
     SimpleMenu(JGE*, int id, JGuiListener* listener, int fontId, float x, float y, const char * _title = "", int _maxItems = 7, bool centerHorizontal = true, bool centerVertical = true);
     virtual ~SimpleMenu();
     virtual void Render();
+    virtual bool CheckUserInput(JButton key);
     virtual void Update(float dt);
     virtual void Add(int id, const char * Text, string desc = "", bool forceFocus = false);
     int getmCurr(){return mCurr;}