Android tv ui improvments

[zeqzy]

For wii games play the video stored in opening.bnr of the selected game and play it in the background
For gamecube games display the text in opening.bnr in the background

When the ui is complete can it be ported to pc ( an option in settings to set default ui or add command line option -tvmode

[Helios]

The Android TV UI can't be ported to anything due to it being written with the Android API, which isn't portable.