The button was broken because it was classified as popover, which
means that the JavaScript code will mess with it. In reality,
*that* button was supposed to point at the actual market:// URL.
So we just remove the class and associated data here to fix that.
Fixes#89.
This allows future App versions to also work with the invite page
without having to screen scrape the content.
Fixes#56 (at least for the portal side of things).
Tester feedback has shown that desktop client users will also
click that button because they are, in fact, not on mobile.
This button speaks more to the users intent (sending the
invitation to the mobile device) after having (hopefully) read
the text above.
Fixes#38.
