Trimming of tracks to remove silence

[GoogleCodeExporter]

Describe the feature you want implemented.
The ability to have Stoffi remove the silence at the beginning and end of songs.

Describe why you think that this feature is needed.
Some songs have a few seconds of silence in the beginning. Similarly some songs 
have a long section of silence at the end of the song. This makes it annoying 
to listen to music when you are faced with sections of silence every now and 
then.

Are there any other projects that inspired you?
Winamp has a plugin which lets the user select to remove all silence in the 
beginning and end of a song. Where silence is defined by a user configurable 
decibel threshold.

Do you have any suggestions on how we could implement, design or present
this feature in an easy and intuitive way?
It can be just a checkbox saying "Remove before and after music".
Stoffi could analyze every song as soon as it's added to the library and mark 
the beginning and end of the sound. These pointers can then be used when 
starting and ending playback of the song.

Original issue reported on code.google.com by ephracis on 18 Sep 2012 at 12:47