Does numbuf make sense as part of pyarrow?

[robertnishihara]

Numbuf (under src/numbuf) is a library for serializing more general Python objects using Arrow.

Questions:

1. Would this make sense as part of pyarrow?
2. Would it be realistic to build a Java equivalent of numbuf?

[robertnishihara]

Note this is being worked on in apache/arrow#965.

[robertnishihara]

This was completed in #910, which removed numbuf from ray.