Separated slot functions from regular interface functions, and added the ability to use KTFrequencySpectrumDataFFTWs.
Added ability for KTCorrelator to deal with KTFrequencySpectrumFFTW.
Added missing comma in AveragePowerSpectrumConfig.json.
Stop KTEvent from printing an error message if it can't find data of a particular name, because this is used in some cases to test if data of a particular type is available.
Fixed a bug in KTPowerSpectrumAverager.
Make CreatePowerSpectrumHistogram in KTFrequencySpectrumFFTW add the negative and positive frequency components.