Update to work with new FT8/MSK144 standards

Ian,

Any chance you'll be updating this program to work with the updated standards for FT8 and MSK144 used in WSJT-X 2.0.0? I'd take a look myself but my C++ is very rusty. :)

Your program seems to decode FT8 signals just fine but it transmits in the old format.

Thanks and 73,
Vinny KB1JDX