Using C++ standard library where possible instead of boost

[ursfassler]

Summary

Using C++ standard library where possible instead of boost.

Details

Many boost functionality moved into the C++ standard library over the years. This PR uses the functionality form the standard library instead of boost.

The minimal required C++ standard is C++17.

Motivation and Context

This is a modernization of the code base.

How Has This Been Tested?

No functional changes were made. All tests run in the CI.

Types of changes

• Bug fix (non-breaking change which fixes an issue).
• New feature (non-breaking change which adds functionality).
• Breaking change (fix or feature that would cause existing functionality to not work as expected).

Checklist:

• It is my own work, its copyright is implicitly assigned to the project and no substantial part of it has been copied from other sources (including Stack Overflow). In rare occasions this is acceptable, like in CMake modules where the original copyright information should be kept.
• I'm using the same code standards as the existing code (indentation, spacing, variable naming, ...).
• I've added tests for my code.
• I have verified whether my change requires changes to the documentation
• My change either requires no documentation change or I've updated the documentation accordingly.
• My branch has been rebased to main, keeping only relevant commits.

[luke-hill]

This should probably live as a new breaking change for whenever the cpp library is released

[ursfassler]

@luke-hill I don't exactly understand what you mean. Do you think we should wait with the changes until a release is done, consider this changes as breaking changes in a new library version or something else?

[mattwynne]

@ursfassler I don't have the knowledge of this codebase to be able to do a decent review of your commits, but given that we don't have anyone else to review this code and you've expressed and interest in helping out as a maintainer I'm going to assume you know what you're doing and merge this. 🚀

In general, I am trying to encourage everyone with commit rights (which you already have 👍🏻) to follow the Ship / Show / Ask protocol. Feel free to ask for feedback if you want it, but don't get blocked if you don't or can't get that feedback.