Unreliable Event boolean in UserSettings

[Jsalam]

eventOnVSettings is a boolean that indicated if any gui element in ControlPanel changed. It is true when the ControlP5.Event is triggered in ControlPanel and it is reset to false at the end of the GraphPad.draw(). It is somehow switching to false before the draw loop completes.

To solve this it is necessary to replace this rudimentary solution with an Observer pattern. Any object that needs update at events on control panel must observe UserSettings event handler (UserSettings.getInstance().setEventOnVSettings())