Add Polygon/Polyhedron NSIDED/NFACED ExodusII output

[ConnorOuellette]

Summary

This adds ExodusII output support for libMesh’s arbitrary polygon and polyhedron elements:

• writes C0POLYGON elements as Exodus NSIDED blocks
• writes C0POLYHEDRON elements as Exodus NFACED blocks
• emits the associated face block, face-node connectivity, face counts, element-face connectivity, and element face counts needed for NFACED output

Notes

• If using ParaView, the default IOSS Reader does not support polygonal/polyhedral input. Please use the Legacy Exodus Reader.
• Fixed an error with build_cube() where corner nodes were scaled twice

[roystgnr]

I'd have split this into like 6 commits instead of 2 (re-bootstrap should be separate, tests could be separate, additional build_cube option should be separate), but the contents look mostly solid. That hardcoded block id (unless I'm just misunderstanding?) is the only thing that looks wrong.

[roystgnr]

These additions look like The Right Way To Do It to me, but I'll want to give @jwpeterson time to chime in before merging; IIRC the ExodusHeaderInfo refactor was an addition of his for Akselos usage.

[roystgnr]

Looks like you turned on some auto-code-reformatting option in your editor? That works within MOOSE, so long as you're pointing clang-format to the MOOSE config file and you're using the right clang-format version, but libMesh doesn't use the same (or any clang-format config-describable) formatting standards, and auto-reformatting utterly wrecked your ff02c5c commit. I can't find the needle of the actual changes in the 4000-line haystack of the reformatting.

As a general safety rule, never git add some/file or git commit -a without git diff to look at the changes first to make sure you're not committing anything you didn't mean to. Even in repos like MOOSE where CI will block formatting changes, it's still easy to accidentally commit diagnostic code, accidentally put multiple distinct changesets into a single commit, etc.