name:etymology contains a description of the name origin and is
thus more informative than search-worthy.
name:signed basically indicates that the feature does not have
a name.
These are used to mark large paved areas. Sometimes they exists
together with named regular streets. In such cases the unnamed
area may overshadow the actual street when computing the address
parent. As unnamed highways are not very useful anyway, we
simply remove them from the database.
Remove unnamed landuses and postcode points from
importing. The latter will cause all objects with
address tags to be imported after all. Not expected
in the admin import style.