Topology does not update in case of added RegionGroup

[Helveg]

When the configuration bootstraps the scaffold's topology is created (does this really need to happen inside of the Configuration._bootstrap method? Would be better inside of the scaffold's, no?). If the topology creates a root RegionGroup, then adding regions/partitions to the network.partitions and network.regions dictionaries does not include them in the topology, and calls to for example network.resize won't affect them.

(Can be worked around with network.topology.children.append and then network.resize())