feat: Allowed an empty reference start and/or end positions

VERSION

-358
+359

lib/+artoa/+controller/+track/+parameter/validateReferencePositions.m

@@ -15,6 +15,10 @@ end
     function [success, message] = validateReferencePosition(position)
         success = false;
         message = '';
+        if isempty(position) | isempty(position{1})
+            success = true;
+            return
+        end
         % transform to cell array
         referencePosition = cellfun(@(x) strsplit(x), position, 'UniformOutput', false);
         % check size of every cell in the array