Define INT96 ordering

[asfimport]

Currently int96 binary ordering doesn't match its natural ordering. We should either specify this or declare int96 not ordered and link to the type replacing it.

Reporter: Julien Le Dem / @julienledem

Related issues:

• INT96 should be marked as deprecated (is related to)

_{Note: This issue was originally created as PARQUET-904. Please see the migration documentation for further details.}