silx view: Opening a group containing datatypes raises a RecursionError

[loichuder]

See for example the group datatypes in the file epics.h5:

maximum recursion depth exceeded while calling a Python object   File ".../silx/gui/hdf5/NexusSortFilterProxyModel.py", line 89, in lessThan
    if self.__isNXentry(left) and self.__isNXentry(right):
  File ".../silx/gui/hdf5/NexusSortFilterProxyModel.py", line 103, in __isNXentry
    class_ = node.h5Class
  File ".../silx/gui/hdf5/Hdf5Item.py", line 108, in h5Class
    if self.__h5Class is None and self.obj is not None:
  File ".../silx/gui/hdf5/Hdf5Item.py", line 91, in obj
    self.__initH5Object()
  File ".../silx/gui/hdf5/Hdf5Item.py", line 212, in __initH5Object
    if not self.isGroupObj():
  File ".../silx/gui/hdf5/Hdf5Item.py", line 139, in isGroupObj
    if self.h5Class is None:
  File ".../silx/gui/hdf5/Hdf5Item.py", line 108, in h5Class
    if self.__h5Class is None and self.obj is not None:
  File ".../silx/gui/hdf5/Hdf5Item.py", line 91, in obj
    self.__initH5Object()
  File".../silx/gui/hdf5/Hdf5Item.py", line 212, in __initH5Object
    if not self.isGroupObj():
  File ".../silx/gui/hdf5/Hdf5Item.py", line 139, in isGroupObj
    if self.h5Class is None:
  File ".../silx/gui/hdf5/Hdf5Item.py", line 108, in h5Class
    if self.__h5Class is None and self.obj is not None:
  File ".../silx/gui/hdf5/Hdf5Item.py", line 91, in obj
    self.__initH5Object()

...etc