Use the macro, not handwritten code, to construct anymultirange_in().
Apparently anymultirange_in was written before we converted all
these pseudotype input functions to use a common macro, and it didn't
get fixed before committing. Sloppy merging probably explains its
unintuitive ordering, too,
Standardize error reports in unimplemented I/O functions.
We chose a specific wording of the not-implemented errors for
pseudotype I/O functions and other cases where there's little
value in implementing input and/or output. gtsvectorin never
got that memo though, nor did most of contrib. Make t