* Add card icon to audio menu items
* Update cache data format
* Create _getCacheItem
* Add _playAudioFromSource function
* Implement default card audio info
* Specify exact audio to download when an override is assigned
* Abstract using _getMenuItemSourceInfo
* Update downloadability check
* Update the main audio menu buttons to also assign the default source
* Move background.html to /
* Move context.html to /
* Move info.html to /
* Move legal.html to /
* Move permissions.html to /
* Move pitch-accents-preview.html to /
* Move popup-preview.html to /
* Move search.html to /
* Move settings.html to /
* Move settings2.html to /
* Move template-renderer.html to /
* Move welcome.html to /
* Move float.html to /
* Move display-templates.html to /
