ENH: Increase itk::FrequencyBandImageFilter class coverage.
ENH: Increase itk::FrequencyBandImageFilter class coverage.

Exercise exception cases: catch expected exception when updating the
filter with a low frequency threshold whose value exceeds that of the
high frequency threshold.

jhlegarreta/ITKIsotropicWavelets,jhlegarreta/ITKIsotropicWavelets,phcerdan/ITKIsotropicWavelets,phcerdan/ITKIsotropicWavelets