Issue #92: Fix MX Player always launching and Ouya main menu.
Allow Normal Screens that can support a 600 dp width to use the app.
Fix screen compatibility to allow some phones and phablets to be used.

This adds the compatible-screens dialog to make sure that only devices
that meet a certain dpi requirement can use the app.  This brings the
list to about 800 devices that could be used.  Doubling it from the 400+
devices before.