Use kernel_id from provider's manager

[kevin-bates]

Update to use the kernel-id generated by the provider. If not set we'll go ahead and assign an id anyway. If we decide to raise an issue (or log a warning), that's fine as well. This approach seemed the least intrusive.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (jupyter-kernel-mgmt@9d3c7e0). Click here to learn what that means.
The diff coverage is 66.66%.

@@                  Coverage Diff                   @@
##             jupyter-kernel-mgmt       #3   +/-   ##
======================================================
  Coverage                       ?   73.63%           
======================================================
  Files                          ?       99           
  Lines                          ?     8894           
  Branches                       ?        0           
======================================================
  Hits                           ?     6549           
  Misses                         ?     2345           
  Partials                       ?        0

Impacted Files	Coverage Δ
notebook/services/kernels/kernelmanager.py	78.1% <66.66%> (ø)

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[takluyver]

Seems reasonable. You may want to make your own PR against notebook so you're not relying on me merging things into my PR.

[kevin-bates]

Good idea regarding making my own PR. I'll do that. (However, I had just added another update to pin tornado to 5.1.1.) I can make that part of my PR if you'd rather we split this now.

[takluyver]

Or I can add you to my notebook fork so you can update the branch, if you prefer. Splitting's not the aim, just avoiding me being the bottleneck.

[kevin-bates]

That's fine too. I appreciate that. I just don't want to get going down the wrong road in the single branch either. That said, I suppose just having one WIP PR for the same thing is probably less confusing to the Notebook maintainers.

Please go ahead and add me to your branch. If there's a change that's too radical, I'll submit a PR to it instead. Does that sound ok?

[takluyver]

That sounds fine. I've added you.