volCComponentCounter bad count

[kerautret]

The count of connected component looks not always correct.
For instance if you try with the following file : bugCCCounter.vol.zip

will produce 4 (instead 3 with background):

volCComponentCounter -i bugCCCounter.vol -c 26 
Image loaded: [Image - STLVector] size=3300 valuetype=1bytes Domain=[HyperRectDomain] = [[PointVector] {313, 366, 86}]x[[PointVector] {332, 380, 96}]
New Block [Initial disjoint sets construction]
EndBlock [Initial disjoint sets construction] (1.627 ms)
New Block [Merging neighboring sets]
EndBlock [Merging neighboring sets] (6.809 ms)
Number of disjoint 26-components = 4