fix(columns): remove columns dynamically with Editors, fixes #406

[ghiscoding]

• when user has Editors and Row Selection, user must rebuild the facade (internalColumnEditor into editor)

[codecov]

Codecov Report

Merging #410 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master   #410   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files         141    141           
  Lines        8849   8855    +6     
  Branches     3052   3053    +1     
=====================================
+ Hits         8849   8855    +6

Impacted Files	Coverage Δ
...modules/angular-slickgrid/services/grid.service.ts	100% <100%> (ø)	⬆️

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