Back to gradle build system

- I got tired of studio complaining that the project was not using gradle
- Add out/ to .gitignore

Signed-off-by: Andy Warner <winc03@gmail.com>
Call onNewSong() from queueSong instead of playSong

Fix 2 irritating bugs:
- The label in "SETTINGS" tab wrapped the ending S
- GL view didn't know the current song most of the time