Update CMakeLists.txt with commented extras
Update README with FFTW
Update example configurations
Preliminary support for FFT in k direction
Improved support for vertical FFT and BC extension
Allow negative angles option for RTZ
Allow negative angles in background load
Add check for missing pressure levels
Add gdwarf-4 flag for newer gdb debugging
Update GeographicLib static calls to functions in v1.37
Removing trailing whitespace in VarDriver
Allow missing dbz, vel, or sw in radar sweepfile

For optimal data analysis the reflectivity, velocity, and
spectrum width will all be available. This allows for fall
speed calculation and better characterization of the error.
Sometimes its not all there though, for example in WSR-88D
split tilts. This change allows the option to read in data
with only one of the three variables. Further changes to
VarDriver3D.cpp are required to handle the missing values.
Add ascii radar type .rad
Fixes for missing dbz, vel, or sw
Fix altitude and missing data for .rad
Bug fixes for missing radar values
Change minimum index for adjustBG pseudo-obs
Fix duplicate ZZ declaration in VarDriver3D