Consider Transit

Currently, among other things, `src/intertypes` defines a translation layer Julia, Python, etc. for commonly used types like `Boolean`, which becomes `Bool` in Julia or `"bool"` in Python, and so on.

Consider `transit` https://github.com/cognitect/transit-format which is:
> Transit is a format and set of libraries for conveying values between applications written in different programming languages. This spec describes Transit in order to facilitate its implementation in a wide range of languages.

A particular up-to-date implementation is this repository: https://github.com/DotFox/transit.c .

So, maybe there is some conceptual or practical overlap here, and we could find some way to serialize ACSets via this means. This could require implementing some Transit library for Julia, which would best happen outside this repo.