Update name relationship type representations and symmetrie
since #7809 it is now possible to store name relationships in both directions.
Many of the direct representations are missing an "is xxx". This is necessary to better distinguish from "has xxx" relations.
Also we need to adapt symmetrie. 4 name relationships are defined as symmetrical (misspelling for, orth. var. for , emendation and nom. alt.). Generally none of the name relationships is really symmetrical. Even alternative names do have a kind of preferred name even if the alternative name is not illegitimate.
We should set all these "symmetric" flags to false.