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## Summary of the Pull Request
It's 2020 now. It's *about* time that we move on from 1990's macros.
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## References
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## PR Checklist
* [X] Closes#4152
* [X] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [ ] Requires documentation to be updated
* [ ] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx
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## Detailed Description of the Pull Request / Additional comments
Remove global namespaced min/max and replace it with STL min/max.
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## Validation Steps Performed
Run it.
dd1dbf5780