Feature/point show per column

[rcbat73]

Add feature requested:
Support point.show on a per-column basis #2683

[codecov-io]

Codecov Report

Merging #2704 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2704      +/-   ##
==========================================
+ Coverage   82.68%   82.69%   +<.01%     
==========================================
  Files          59       59              
  Lines        4718     4726       +8     
==========================================
+ Hits         3901     3908       +7     
- Misses        817      818       +1

Impacted Files	Coverage Δ
src/core.js	90.86% <100%> (-0.05%)	⬇️

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