Clarify this project's development and maintenance status

[snarfed]

Hi all! Reposting #765 (comment) here as a new issue. Hope you all don't mind.

Some work on this project is clearly happening, primarily by @rwhogg. Great, thank you! We really do appreciate it.

It's not a lot, though. Details below.

I don't mean to be ungrateful. ndb is awesome, many of us have obviously used and benefited it for decades (!) now. Thank you! However, for those of us still actively building and maintaining our own projects on ndb, it's important for us to understand the maintainers' (ie Google's) level of ongoing commitment and investment here.

Will this project eventually be sunsetted? Will it continue on with minimal support? Or is there a path toward you all engaging more actively here? Any answer is ok! But if we want a datastore client library that's more actively maintained, do we need to start planning to eventually migrate to the official datastore client, or another library?

Thanks in advance.

--

Looking at recent PRs, the vast majority are administrative or chores: docs, tests, dependencies, other minor refactorings and cleanups. Which are good! But of the ~100 PRs over the last year, it looks like just five are actual bug fixes or otherwise noticeable code changes: #882, #877, #873, #852, #815.

That may be OK. Development on a mature, actively maintained project can be slow, and still reasonable. But looking at the ~25 issues filed over the last year, many of which are real bugs or problems, it looks like only five received any response at all from maintainers - #911, #897, #862, #836, #804 - and three of those were filed by maintainers themselves.

Previously: #816, #765 etc

[pnico]

Does use of this library essentially rule out use of async clients from the other python cloud client libraries?
#289 was closed as wont-fix citing backwards compatibility concerns, but I wonder if this is outweighed by the possibility that using it could create its own kind of legacy lock-in situation.