Investigate pickle 5 protocol for extending design space for zero-copy

[sighingnow]

Describe your problem

I just know that apache-arrow will deprecated the serialization implementation and move to pickle5 (ARROW-11463).

We need to check if that is suitable for vineyard.

**Notes about pickle 5

This PEP aims to make pickle usable in a way where large data is handled as a separate stream of zero-copy buffers, letting the application handle those buffers optimally.

Pretty like what we have in vineyard: an object consists of a metadata and a set of blobs...

Additional context

See also: #184
And:

• https://github.com/pitrou/pickle5-backport
• https://www.python.org/dev/peps/pep-0574/

[sighingnow]

Serialization using the new pickle in mars: https://github.com/mars-project/mars/pull/1937/files