Revert "Fix missing first element in index."

Incorrect diagnosis, this is not the cause of the issue mentionned.

It does though introduce a possible empty cells, which violates
assumptions.

Revert and comment.

This reverts commit b784e2fed0.

src/cell_space.rs

@@ -63,14 +63,15 @@ where
         for coordinate in distinct {
             //trace!("{:?} {:?} {:?} {:?}", dimension, coordinate, cell, count);
 
-            cells[cell].push(coordinate);
-            count += 1;
-
+            // Check first, otherwise we might add a cell which will stay empty.
             if count == max_offset {
                 count = 0;
                 cell += 1;
                 cells.push(Vec::with_capacity(max_offset));
             }
+
+            cells[cell].push(coordinate);
+            count += 1;
         }
 
         info!(