Fix: empty column is added when data row doesn't ends with COLUMNSEPARATOR

[tlukkezen]

A new and empty column is added when the rows in the cpt data end with solely the column-separator value (in _GefCpt.parse_data())

The last (redundant) column separator is only removed when it is followed by "!"

Solution

Data records should always be stripped of trailing Column AND Record separators, even if one of them is not present.