added FFT option in sweep benchmark example
Added ppb
Merge branch 'master' of https://github.com/jgobuyan/pyrf
CAPTURE_FREQ_RANGES is 4k-only
Merge branch 'master' of https://github.com/pyrf/pyrf
added iq output path controls, GUI will remove unnecessary controls when using an external digitizer
added MHz labels to frequency controls
removed fshift and dec controls when in CONNECTOR IQ path mode
removed sample small sample sizes from sweep benchmark
fixes to sweep_benchmark.py + ppb arg
sweep device: prevent -ve step count