minimodem.js

At this moment the sending and receiving audio interface is almost done (improvements are really welcome).

The system is able to send an arbitrary array of bytes using the following modulation and codification schemes:
- BASK
- BFSK
- QFSK

The decoding submodule is under develoment...

The ToDo List includes:
- Recruit partners!!
- Improve the spectrogram representation (maybe too slow...)
- Implement an efficient receiving and decodig subsystem
- Improve layer 1: add more MCS
- Create layer 2: a MAC layer to add redundacy/error detection/error correction codes.
- Explore beyond the simplex mode... is a half duplex mode possible in order to feedback the error dectection and generate retransmisions?