added clear Cache on Exit

this is version 2 of https://www.emailnator.com/ web wrapper. I added the ability to clear the cache Every time you exit the app because it was messing up and not letting you gerate emails. After update, be sure to back out of the app so it closes and the cache should clear automatically. As mentioned before I did not create this just used web2app generator to make a web wrapper. I claim no rights and make absolutely no profit. don't expect updates, I didn't anticipate on making this, but it was annoying that it stopped working. I only make these for myself and share with the world if they share my interest.