Fixed bug when a cluster group is an array in the HDF5 file.
Fixed bug when a cluster group is an array in the HDF5 file.

kwikteam/phy,rossant/phy,rossant/phy,nippoo/phy,kwikteam/phy,kwikteam/phy,nsteinme/phy,nsteinme/phy,nippoo/phy,rossant/phy