Feature: Add Reverb

[composition4]

This, as a placeholder for coming PR (and discussion).

[neauoire]

Sure :)

[composition4]

Issues with fileIO at the moment prevent convolution filter as well as possible conflict of licensing & dependency on impulse data (ogg).

Aside from simple echo provided, article recommends using FFT/blur to handle simple reverb (also mentions using multiple delay streams).

Suggest initial prototype using FFT, avoiding blur for now until further testing proves its requirement. I'll work on this as best as possible however refactoring of jammer.js & player-worker.js may eventually need to be done for handling stream data more efficiently.