Allow Download of Application APKs

Well, the title speaks for Itself. This would be a great **feature** in this gem. What I'm actually looking for is a Ruby Equivalent of http://code.google.com/p/android-market-api/ which allows you to download the APK.

It may require the user to add his PlayStore registered Email/Password along with his Android Device ID.

Thanks and Awesome Gem btw.
