Isolated GE inverse distortion optimization

This is the first, most initially impactful optimization, which replaces the fsolve GE inverse distortion with a simple numpy-based Newton's method. The distortion correction is well-suited to Newton's method because of how well-behaved of a function it is.

In follow-on optimization, we implemented a Numba version of this, inlining the distortion function into the solver, which provided further speedups.