Add Clang-Tidy checks for case conventions, including our math conventions

[KipHamiltons]

We could enforce naming conventions with built in clang-tidy checks.
We could also build custom checks for our codebase, including ones that enforce our math naming conventions.
An implementation of such checks might simply check the types of the tokens then make sure that if it's an eigen matrix, that it's named properly. You might even be able to make sure that compatible matrix multiplications are the only ones that happen. The options are endless 😅