use setuptools find_packages, exclude tests, docs and examples from dist

[bollwyvl]

This:

• removes the confusing, deprecated find_packages from setupbase.py
• imports and uses the real setuptools.find_packages to exclude things that might be python-module-like

In site-packages/, tests/, docs/, etc. are dumping grounds of all the packages that either don't use this flag. In this state, it's not even worth distributing them, as there's basically zero chance they'll work. Putting them in-tree, on the other hand, is very nice, as downstreams can ensure that their packages work, which helps catch issues sooner, but that's for another day...

[bollwyvl]

oh, and we may need to add a temporary pin for jedi... ipython/ipython#12751

[codecov-io]

Codecov Report

Merging #368 (e59b4ab) into master (1f5508e) will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #368      +/-   ##
==========================================
+ Coverage   69.29%   69.30%   +0.01%     
==========================================
  Files          56       56              
  Lines        6135     6135              
  Branches      804      804              
==========================================
+ Hits         4251     4252       +1     
  Misses       1616     1616              
+ Partials      268      267       -1     

Impacted Files	Coverage Δ
jupyter_server/services/kernels/handlers.py	58.51% <0.00%> (+0.26%)	⬆️

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[bollwyvl]

Cool (i guess) looks like jedi's not breaking anything...

[kevin-bates]

LGTM and makes sense - thanks Nick. I'd prefer that someone more familiar with packaging/distribution than myself to review this as well prior to merging though.

[blink1073]

Thanks!