Only look for submarines when alpha == 1

This is because the submarine detection code runs Michel, which can take a
while.  Upstream code can call this function multiple times with different
alphas, but we only want to call the slow Michel code once.

A better solution would probably be to refactor things to make the calling code
smarter, but at least this makes things better for the time being.

src/MATLAB/+Segmentation/PartialImageSegment.m

@@ -50,6 +50,7 @@ function [hulls features] = PartialImageSegment(img, centerPt, subSize, alpha, t
     
     [objs objFeat] = Segmentation.FrameSegmentor(subImg, 1, alpha);
     
+    if alpha == 1 % hack to keep from running this slow code multiple times
         if strcmp(CONSTANTS.cellType, 'Hemato')
             [hemObjs, hemObjFeat] = Segmentation.HematoSubmarineFrameSegmentor(subImg, 1);
             objs = [objs hemObjs];
@@ -65,6 +66,7 @@ function [hulls features] = PartialImageSegment(img, centerPt, subSize, alpha, t
             objs = [objs flObjs];
             objFeat = [objFeat flObjFeat];
         end
+    end
     
     [hulls features] = fixupFromSubimage(coordMin, img, subImg, objs, objFeat);
 end