Tracking issue: Porting the MINPACK implementation

[rust-cv]

Tracking issue: Porting the MINPACK implementation

[vadixidav]

This is really awesome, and I appreciate the work you are putting in here! This will put us in a good position to have fast and robust camera tracking.

[jannschu]

Just a quick update on the state of this: I added almost all the test functions I wanted and after some intensive debugging everything indicates now that the implementation produces the same floating point output as MINPACK. Some of these changes are behind are feature flag, though. The test cases now pass with the real output of MINPACK which is a bit crazy/unnecessary to be honest, but I was curious.

In the process I also noticed that the finite difference scheme I implemented was below what's possible. I tried three different adaptive finite difference algorithms, one was ported from ALGOL 60 which was no fun. I will now try one final algorithm which from the first tests seems promising and then pick the best one.