Async support?

[afeld]

Moving @macmichael01's question here from #98 (comment):

I forked this project to update it with async ability httpx with sync as the default fallback for backwards comparability. Likely needs some more testing. Would there be interest in pulling this in a release at some point?
https://github.com/rapidrabbitsoft/sodapy-async

[afeld]

I'm open to adding async support, so long as the added complexity is minimal. Looking at your changes, the sync vs. async have separate code paths, which could lead to subtle behavior differences (bugs).

I haven't used httpx before, but it says that it supports "Standard synchronous interface, but with async support if you need it." I'm open to switching to httpx in place of requests, assuming that would require a smaller amount of divergence for the sync vs. async code.

All that said, there are higher-priority items for v3, so this might be a v3.1 or v4 thing.

Thoughts?