Separate channel spectrum config from spectrum data. This will permit sending config info only when necessary.
Use type information of ChannelSpectrum to statically define number of FFT bins elsewhere.
TODO: Posting configuration message way too often. Fixing that is the next step.
More kludginess, especially around initialization and timing. But it addresses the flickering lines of pixels at the bottom of the waterfall scroll area!
Move channel filter frequency determination to baseband side, where the filtering is determined and performed.
Add useful accessor methods to BlockDecimator.
Channel spectrum decimation now accounted for when computing filter frequencies.
Renamed a bunch of variables relating to channel spectrum bandwidth and filter frequencies.
