Rewrite sound module

[ekelokorpi]

Lots of room for optimization, cleaner code, better syntax.

[ellisonleao]

How about using https://github.com/goldfire/howler.js/ ?

[ekelokorpi]

Hmm, I really want use external libraries as little as possible, just to keep control of how everything works.

And i'm almost done rewriting the module :)

Though Howler features look pretty nice :+1:

[ekelokorpi]

First version ready: https://github.com/ekelokorpi/panda.js/blob/develop/src/engine/audio.js

Syntax:

// Add audio to loader
game.addAudio('media/jump.m4a', 'jump');

// Play audio as a sound
game.audio.playSound('jump');

// Define volume
game.audio.playSound('jump', 1.0);

// Loop sound
game.audio.playSound('jump', 1.0, true);

// Define callback
game.audio.playSound('jump', 1.0, true, function() {
    console.log('Audio played');
});

// Define playback rate (only in Web Audio)
game.audio.playSound('jump', 1.0, false, false, 0.5);