[Dx4win] new mode

[Jim Reisert AD1C]

JS8 was added to the ADIF specification 3.0.9 that was recently
approved.  JS8 was added as a sub-mode of MFSK:

    http://www.adif.org/309/ADIF_309.htm#Submode_Enumeration

This does not change the fact that DX4WIN will need an update to
accept this sub-mode.

-- 
Jim Reisert AD1C, <jjreisert at alum.mit.edu>, http://www.ad1c.us