## Motivation

What was the reasoning behind this change? Please explain the changes briefly.

## How to test the behavior?
```
Show here how to reproduce the new behavior (can be a bug fix or a new feature)
```

## Checklist

- [ ] Have you checked our [Contributing](https://github.com/NeurodataWithoutBorders/pynwb/blob/dev/docs/CONTRIBUTING.rst) document?
- [ ] Have you ensured the PR description clearly describes problem and the solution?
- [ ] Is your contribution compliant with our coding style ? This can be checked running `flake8` from the source directory.
- [ ] Have you checked to ensure that there aren't other open [Pull Requests](https://github.com/NeurodataWithoutBorders/pynwb/pulls) for the same change?
- [ ] Have you included the relevant issue number using `#XXX` notation where `XXX` is the issue number ?
