Jsonparse

- Official python 3.13 support. Updated docs and CI.

- Python 2.7 compatibility :astonished: What can I say, I like compatibility. That's one thing about perl(5) I like.
- v2/3 type hint convention.
- OrderedDict should be used if ordering is important as 2.7 dictionary's don't guarantee order.

- Fixed bug where the `find_value` function import was missing from `__init__`, causing a from `jsonparse` import `find_value` to fail.

Added a new `find_value` function. This will return all keys with the associated value.

A good example for this is to find all keys that have a null value, ie in the library, simply `find_value(data, False)`

See the README here:
- https://github.com/ctomkow/jsonparse?tab=readme-ov-file#find_value

Offical python 3.12 support. Updated docs and tests.

- Added functions so no need to create a Parser object, simply import. However, the Parser object still works fine.

`from jsonparse import find_key, find_keys, find_key_chain, find_key_value`