Added further init elements to Sim and Group.
Added further init elements to Sim and Group.

So that our accessors work even before universes (Sims) and members
(Group) have been added, we needed to initialize some structures in the
state file. Now structure is more consistent over the life of the file.

datreant/datreant,andreabedini/datreant,datreant/datreant.data,datreant/datreant.core,datreant/datreant.core,dotsdl/datreant,datreant/datreant