[score][load] Always sort scores when sort=True

Fixes a bug introduced in !258 where scores were not being sorted
when the file was a csv file.

bob/bio/base/score/load.py

@@ -387,8 +387,8 @@ def split(filename, ncolumns=None, sort=False):
         the ``real_id`` are identical (see :py:func:`four_column`)
     """
     if iscsv(filename):
-        return split_csv_scores(filename)
-
+        neg, pos = split_csv_scores(filename)
+    else:
         ncolumns = _estimate_score_file_format(filename, ncolumns)
         if ncolumns == 4:
             neg, pos = split_four_column(filename)