How To Cross-fade

[duysqubix]

This looks like a great library for playing audio, very simple.
One feature that I don't see by looking through the code or docs is how to cross-fade.
I would like to create an app that plays a playlist, playlist can be modified on the fly.
I would like to cross-fade by x seconds.
Bonus points if we can remove silence or levels under x dB.
Is this possible?
If not, is this something that could be added?

Original issue: faiface/beep#44

[MarkKremer]

Cross-fading is underway. I've created a new issue to track removal of silence: #142