Decouple dataflow in ratatool-scalacheck

[RustedBones]

Do not import class that may be missing from user's classpath

Compute key size using machine memory instead of CPUs

[codecov]

Codecov Report

Attention: Patch coverage is 44.44444% with 10 lines in your changes are missing coverage. Please review.

Project coverage is 70.74%. Comparing base (499dbad) to head (2725450).

Files	Patch %	Lines
...ala/com/spotify/ratatool/samplers/BigSampler.scala	44.44%	10 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #717      +/-   ##
==========================================
- Coverage   70.99%   70.74%   -0.26%     
==========================================
  Files          44       44              
  Lines        1824     1839      +15     
  Branches      292      316      +24     
==========================================
+ Hits         1295     1301       +6     
- Misses        529      538       +9     

Flag	Coverage Δ
ratatoolCli	2.87% <0.00%> (-0.04%)	⬇️
ratatoolCommon	0.00% <ø> (ø)
ratatoolDiffy	32.51% <0.00%> (-0.32%)	⬇️
ratatoolExamples	17.22% <0.00%> (-0.16%)	⬇️
ratatoolSampling	61.78% <44.44%> (-0.30%)	⬇️
ratatoolScalacheck	79.34% <ø> (ø)
ratatoolShapeless	4.14% <0.00%> (-0.05%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.