Have HAL detect audio players like rhythmbox does - with a .is_audio_player file

There are many different kinds of portable mass-storage audio players, and putting all of them in HAL's fdi specification would be inefficient. The major players should indeed be placed there, but for more minor players - it would be nice if, instead of having rhythmbox check for a ".is_audio_player" file on the device - hal would, and then register the device as an audio player, so all programs can check this through HAL. I also propose having Nautilus detect a device with many audio files on it, and asking the user whether the device is a portable player - if he answers yes, the ".is_audio_player" file should be created. Otherwise, a stub ".is_not_audio_player" file should be created so the question isn't asked again.

A good example is syncropated - this application only works with audio players which HAL recognizes, and it took me a while to figure out how to make it do that.