Group information in new database not stored

[Siedlerchr]

Current master.

I debugged a bit through and found that in the MetaDataSerializer.getSerializedStringMap the metaData.getGroups() returns null/empty optional. In the metadata class the groupsRoot is null.

Furthermore I found out that setGroups() in Metadata is never called (except from the importer and some tests)

[lenhard]

So at what point in the code are the new groups (most important the root) actually created? I had a look at the code and have a hard time finding it.