Add separate min and max frequencies to KTSpline to hold the min and max frequencies from the power spectrum that went into the averages for the end points of the spline.  Set the min and max frequencies in KTGainVariationProcessor.  At this point the min and max frequencies are only used to draw the gain variation data.
Fixed a bug in the record reading that called ReadRecord incorrectly when using stride != slice size.
Merge branch 'refs/heads/Maintenance' into WFAnalysis