Patrick Dohmen authored Mar 27, 2018 and Manolis Surligas committed Jul 18, 2018

Add a BPSK decoder script for frames transmitted in AX.25, using G3RUH
scrambling and without. Baudrate is set via parameter "baudrate", all
filters, taps, offsets, etc are calculated using this parameter. Decoder
tested with 1k2 bps and 9k6 bps.