Changing defaultTouchPriority for CCControlColourPicker does not propagate to children controls

[TinyRob]

If you create an instance of CCControlColourPicker and then wish to change the touch priority for it, the effect is lost because the ivars "colourPicker" and "huePicker" do not get their defaultTouchPriority changed.

A simple fix for this would to just override the setter in CCControlColourPicker to look like this:

-(void) setDefaultTouchPriority:(NSInteger)defaultTouchPriority
{
    [super setDefaultTouchPriority:defaultTouchPriority];
    [_huePicker setDefaultTouchPriority:defaultTouchPriority];
    [_colourPicker setDefaultTouchPriority:defaultTouchPriority];
}