Root folder doesn't show attributes

[dritory]

The root folder (root/) doesn't show attributes that are stored at the root folder.

`def main():
filename = Path('test_data/sample.hdf5')
with h5py.File(filename, 'w') as f:

    f.attrs["name"] = "demo"
    ...

`
Should produce a "name": "demo" attribute in the hdf5 viewer.