Merge suggestion of PR "Reordering hidden columns #185" from ember-headless-table #59

I've successfully patched the PR "Reordering hidden columns #185" CrowdStrike/ember-headless-table#185 for ember-headless-table in production for a while, and would like to propose this PR as "ready for merge" for universal-ember/table

It says "WIP" on the PR, but I approve as working with functional testing at least!