stereo_pprc: Take another stab at AA reduce (no edge blending)
stereo_pprc: Take another stab at AA reduce (no edge blending)

This version should preserve the edge of *-L_sub.tif. It appears the
edge of *-R_sub.tif is already blended.

aaronknister/StereoPipeline,ScottMcMichael/StereoPipeline,aaronknister/StereoPipeline,njwilson23/StereoPipeline,NeoGeographyToolkit/StereoPipeline,njwilson23/StereoPipeline,NeoGeographyToolkit/StereoPipeline,ScottMcMichael/StereoPipeline,njwilson23/StereoPipeline,NeoGeographyToolkit/StereoPipeline,DougFirErickson/StereoPipeline,ScottMcMichael/StereoPipeline,njwilson23/StereoPipeline,oleg-alexandrov/StereoPipeline,DougFirErickson/StereoPipeline,oleg-alexandrov/StereoPipeline,ScottMcMichael/StereoPipeline,NeoGeographyToolkit/StereoPipeline,aaronknister/StereoPipeline,NeoGeographyToolkit/StereoPipeline,DougFirErickson/StereoPipeline,njwilson23/StereoPipeline,DougFirErickson/StereoPipeline,oleg-alexandrov/StereoPipeline,aaronknister/StereoPipeline,oleg-alexandrov/StereoPipeline,oleg-alexandrov/StereoPipeline,njwilson23/StereoPipeline,oleg-alexandrov/StereoPipeline,ScottMcMichael/StereoPipeline,NeoGeographyToolkit/StereoPipeline,aaronknister/StereoPipeline,DougFirErickson/StereoPipeline,DougFirErickson/StereoPipeline,ScottMcMichael/StereoPipeline