doc: A minor blub on advantage of merging dems when there are multiple images
doc: A minor blub on advantage of merging dems when there are multiple images

ScottMcMichael/StereoPipeline,oleg-alexandrov/StereoPipeline,ScottMcMichael/StereoPipeline,NeoGeographyToolkit/StereoPipeline,ScottMcMichael/StereoPipeline,NeoGeographyToolkit/StereoPipeline,oleg-alexandrov/StereoPipeline,oleg-alexandrov/StereoPipeline,NeoGeographyToolkit/StereoPipeline,ScottMcMichael/StereoPipeline,NeoGeographyToolkit/StereoPipeline,oleg-alexandrov/StereoPipeline,ScottMcMichael/StereoPipeline,oleg-alexandrov/StereoPipeline,NeoGeographyToolkit/StereoPipeline,ScottMcMichael/StereoPipeline,oleg-alexandrov/StereoPipeline,NeoGeographyToolkit/StereoPipeline