Anacreonlib

Update to pydantic 2

This is a beta release because the handling of AEON IP integers is less robust now (my hand was forced due to Pydantic API changes :/ ), but hopefully passable for the time being!

fix some deserialization issues
- `maxTradeRoutes` is now optional for `OwnedWorld`
- `targetTechLevel` and `targetPopulation` have been added as optional fields to `World`

The old version of anacreonlib, first published on github in 2018, was kind of bad for several reasons

- Everything was a dict which was directly retrieved from the Anacreon API
- You were forced to vendor `anacreonlib` as a dependency inside your project
- Documentation about what fields were actually contained inside objects was basically non-existent

I have spent some time basically rewriting anacreonlib from scratch

high level overview of what's new
- uses `asyncio`, so you don't have to use threads for concurrency
- there is [actual documentation](https://anacreonlib.readthedocs.io) you can go read
- supports type checkers like `mypy`
- uses `pydantic` to deserialize JSON values coming in from the Anacreon API into real Python objects (i.e you get IDE autocomplete on them)
- you can install using pip now (instead of extracting a zip file into your repo)