STYLE: Fix indentation in .hxx files.
STYLE: Fix Butterworth definitions.
BUG: Butterworth ThreadedGenerateData should only populate outputRegionForThread.
COMP: Unused variables in LogGabor.
STYLE: Definitions in LogGabor.
STYLE: SteerableFilterFreq definitions.
COMP: Unused variables in SteerableFilter.
STYLE: PhaseSymmetry definitions.
COMP: Unused variables in PhaseSymmetry.