BUG: Using segmentation application with non valid ESRI WKT returns exception when using vector mode with .shp output.

BUG: OGR SpatialReference is first morphed to ESRI when using segmentation filter with .shp output. Thus comparison mst be added in Initialize method. Mantis ref #567

     Used in inherited class for example to implement a simpler
     GetPixelDescription method.

std::map loop using for is wrong in GetMeanIntensity() when dealing wth labelimage which contains non contiguous labels. Mantis #ref564