Added Jacobians for Rot3::RzRyRx and related named constructors

[Eskilade]

Hello :)

The title sums it up. I guess the motivation is pretty straightforward as well : These derivatives are useful for when you want to propagate uncertainties related to Euler angles.

Btw, I've used clang-format with style=Google on my diffs. Let me know if you're using a different formatting tool

[dellaert]

Very useful, many thanks !!!!! I’ll merge once CI passes.

[dellaert]

Unfortunately, one small snag: does not compile when quaternions are selected. Probably a small change, as derivatives should be identical.

[dellaert]

Yay!