Perpendicular is not the same as not parallel

[jdthorpe]

The current implementation of "#Z" is the same as "not |Z", which is not the same as perpendicular.

[codecov]

Codecov Report

Merging #882 (e38f9ee) into master (94030ad) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #882      +/-   ##
==========================================
- Coverage   95.88%   95.88%   -0.01%     
==========================================
  Files          32       32              
  Lines        7654     7652       -2     
  Branches      815      815              
==========================================
- Hits         7339     7337       -2     
  Misses        186      186              
  Partials      129      129              

Impacted Files	Coverage Δ
cadquery/selectors.py	98.12% <100.00%> (-0.02%)	⬇️

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[adam-urbanczyk]

Hm, the current implementation looks weird.

[jmwright]

Thanks @jdthorpe

[adam-urbanczyk]

Thanks for the patience and your contribution @jdthorpe !