Compatibility with pydicom v3

[medihack]

Now that pydicom v3 has been released, what is the plan for pynetdicom? Will an upcoming pynetdicom v2 release support v2 and v3 of pydicom in the future, or will there be a v3 release of pynetdicom that will only target pydicom v3?
I gave it a quick shot to make pynetdicom compatible with pydicom v3 and the few errors in the tests were easy to fix, but there are quite a lot of warnings.

[scaramallion]

I will probably only support pydicom v3+ in the next release.

[medihack]

I am unsure if it helps, but I modified the code and the tests to be compatible with Pydicom v3 with PR #972. All tests pass (at least under Ubuntu), and there are no warnings any more. I still tagged it as WIP because, as a possible first-time contributor, I am pretty sure I overlooked something (it was much too straightforward).

EDIT:
As expected, it's a bit trickier than I thought (see comment in the PR).