setColWidths() supports 0-len cols

[shrektan]

Closes #128

Thanks!

[codecov-io]

Codecov Report

Merging #129 (e4faaa6) into master (8b958b7) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #129   +/-   ##
=======================================
  Coverage   62.53%   62.54%           
=======================================
  Files          30       30           
  Lines        8753     8754    +1     
=======================================
+ Hits         5474     5475    +1     
  Misses       3279     3279           

Impacted Files	Coverage Δ
R/wrappers.R	49.36% <100.00%> (+0.03%)	⬆️

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