Support curves in xdmf files

[markcmiller86]

Description

Resolves #19398

Also includes #19903 merged into this branch to fix spelling error, refactor all instances of strcasecmp, and improve performance of CaseInsensitiveEqual and extend for char const * too.

Type of change

• [ ] Bug fix
• [x] New feature~~
• [ ] Documentation update
• [ ] Other

How Has This Been Tested?

Reminders:

• Please follow the style guidelines of this project.
• Please perform a self-review of your code before submitting a PR and asking others to review it.
• Please assign reviewers (see VisIt's PR procedures for more information).

Checklist:

• [x] I have commented my code where applicable.~~
• [x] I have updated the release notes.~~
• [x] I have made corresponding changes to the documentation.~~
• [ ] I have added debugging support to my changes.
• [x] I have added tests that prove my fix is effective or that my feature works.~~
• [ ] I have confirmed new and existing unit tests pass locally with my changes.~~
• [ ] I have added new baselines for any new tests to the repo.~~
• [x] I have NOT made any changes to protocol or public interfaces in an RC branch.~~

[markcmiller86]

Minor change requested. Have you run the xdmf regression tests to verify that changes to the file format haven't caused any issues?

Not yet. Wanted to get people's take on what I've done so far.

[markcmiller86]

Did you actually make a change to Fusion_vis10.pdf? If so what was it?

Oh, yes. I was trying to minimize disk usage and saw that this file was HUGE. Well, a lot bigger than it needed to be. I PDF optimized to 20x smaller than it was before.