Enable clang-tidy miscellaneous checks

[Baltoli]

This PR enables the "miscellaneous" set of clang-tidy checks. Adopting these checks requires basically no changes to our code, but I've left the following checks disabled:

• Disallowing recursion
• Disallowing unused parameters with names (e.g. this check prefers T f(A, B) to T f(A a, B b) when a and b are unused).
• Using public data members in classes; we do this in a few places and I think it's an acceptable decision.

As ever, happy to bikeshed but this shouldn't be a controversial one at all.