When reading file, allow matching TimeSeries ancestry attribute even if its not an array.  Make unidentified custom nodes inside a custom node a warning not an error.
When reading file, allow matching TimeSeries ancestry attribute even if its not an array.  Make unidentified custom nodes inside a custom node a warning not an error.

NeurodataWithoutBorders/api-python,NeurodataWithoutBorders/api-python,NeurodataWithoutBorders/api-python