Changed the decoder a bit; cons diag should be more useful now
Lots of experimentation with TXer.

Trying to create "path effects" to simulate those experienced on RF path.
Thus far, the decoder can handle the simulated effects, but not the real RF
 path.  I am not sure what kind of distortion the RF path has been creating.
AFC: reduce tuning rate to avoid overshoot
Added ability to read from a wav file, and improved AFC (by a lot!)
Make WAV support optional (-DWAVLIB to enable)
AFC: Faster convergence (in coarse mode)