Statistical info on track popularity

[mzgajner]

Track popularity information could be provided to the user when he is searching for tracks and building a playlist (e.g. how many times the track has been played or when it was last played).

Specific warnings about unwanted situations could also be added (e.g. Don't add this track, it has already been played 3 times this week.).

The music department should provide specific requirements for this enhancement.