Fix review link

Launches the correct review page for the app. Previously this button just launched the Store without prompting for a review.

Just so I know, have you tested this change on Windows 8.0 and later? I ask because that block is using a IF WIN_RT conditional compile so it will apply to multiple builds.

I don't have a Win8 machine to test on, but this is the best way I've found on Win10.

One note: the "FamilyName" API which I use should work on Win8 and WinPhone8.1. What I'm not confident about is the URI scheme. Do you have a macro that can be used to version the URI scheme?

https://msdn.microsoft.com/en-us/windows.applicationmodel.packageid.familyname