Basic Reverb

A Rust implementation of the reverb presented at Let's Write A Reverb. It was made basically translating the reverb example code.
It has differences tough:

• It has a fixed number of channels
• It does not include the examples of intermediary steps to come up with the final reverb.
• It uses a simpler delay (the original it is part of a separate library).
• It doesn't have the configure functions so the sample rate can't be changed once set.