Fldigi versions

v4.0 [Mar 29, 2017]
- clock_gettime
- Change np-compat.m4 to provide for conditional
- use of library calls to clock_gettime
- allow for compiling on OS X < 10.12 using
- Xcode 8.xxx
- use ./configure --without-clock_gettime
- spectrum display
- Changed from fft mode to spectrum display paradigm
- spectrum display available independent of digital mode in use.
- spectrum display dialog opens from "View" menu
- removed all code relating to the original fftscan modem
- added new fltk widget, spectrum based on fldigi's
- digiscope widget
- Test Signal Dialog
- Correct IMD range controls
- dxcluster fonts
- fix dxreport font rendition
- add resizable groups to correctly resize tabs
- Spot buffer
- add clear RE buffer after a successfull match
- Winkeyer clones
- added longer time out for character echo.
- RX Text capture
- Fix loss of capture when Rx text scrolls or user's
- mouse clicks off of the target
- PSK s/n imd
- Changed s/n display code to avoid displaying misleading values
- Changed Noise/Offset/IMD test signal generator
- IMD can be specified in dB and signal will correctly emulate
- an over driven transmit signal.- IMD generator modified to
- correctly computer 3rd, 5th, 7th and 9th- harmonics of PSK
- fundamental (15.625 Hertz).
- Removed "--noise" command line parameter
- Added Test Signal Dialog with
- S/N
- IMD
- tx freq offset
- controls
- disabled display of Rx IMD, s/n values if |imd| > |s/n|
- PSK viewer
- Added the following modes to the multi-channel viewer
- PSK31, PSK63, PSK63F, PSK125, PSK250, PSK500
- PSK125R, PSK250R, PSK500R
- QPSK31, QPSK63, QPSK125, QPSK250, QPSK500