title: Donation in Windows Phone application
body: <p>I have an application for windows phone and its free. I want it to stay free and without ads. But sometimes i need motivation. What i need to do is to add some "buy a pint of beer to the author" button in my application (something like donation button). Sure i can create 2 versions: paid and free that are completely identical in functions just the paid with some "thanks" words, but that will be 2 completely different applications and i'll need to support them both. So..Is it possible to implement some donation payment in the application?</p>