CarpetHDF5 Writer lacks Dataset support

from rug:

        realname = hfile["Parameters and Global Attributes/Datasets"].value.decode("ascii")[:-1]

lacks dataset name

sven@nils:/tmp/hdf5$ rug window -f 'log10(y)' whatever.h5  0
Traceback (most recent call last):
  File "/home/sven/bin/rug", line 265, in <module>
    modules.call(args)
  File "/home/sven/numrel/ET/rugutils/modules.py", line 68, in call
    return function(**given_args)
  File "/home/sven/numrel/ET/rugutils/window.py", line 173, in window
    realname, struct = read_file_structure(hfile, name)
  File "/home/sven/numrel/ET/rugutils/read_hdf5.py", line 165, in read_file_structure
    realname = hfile["Parameters and Global "
  File "h5py/_objects.pyx", line 54, in h5py._objects.with_phil.wrapper (/build/h5py-qzs83i/h5py-2.7.1/h5py/_objects.c:2847)
  File "h5py/_objects.pyx", line 55, in h5py._objects.with_phil.wrapper (/build/h5py-qzs83i/h5py-2.7.1/h5py/_objects.c:2805)
  File "/usr/lib/python3/dist-packages/h5py/_hl/group.py", line 167, in __getitem__
    oid = h5o.open(self.id, self._e(name), lapl=self._lapl)
  File "h5py/_objects.pyx", line 54, in h5py._objects.with_phil.wrapper (/build/h5py-qzs83i/h5py-2.7.1/h5py/_objects.c:2847)
  File "h5py/_objects.pyx", line 55, in h5py._objects.with_phil.wrapper (/build/h5py-qzs83i/h5py-2.7.1/h5py/_objects.c:2805)
  File "h5py/h5o.pyx", line 190, in h5py.h5o.open (/build/h5py-qzs83i/h5py-2.7.1/h5py/h5o.c:3738)
KeyError: "Unable to open object (object 'Datasets' doesn't exist)"