Rustworkx acceleration

[InnovativeInventor]

This is a draft PR (based off perf-tuning that rewrites the balance edge picking algorithm in Rust using retworkx, yielding a ~16x speedup in chain run times).

PA chain run times (congressional) are now at 50 it/s on my computer with commit e9eddbef5b82522e4d1d3c12e68d35958fb1cae9 (as opposed to ~3 it/s). This also leaves a few more low-hanging fruit optimizations on the table which could yield more speedups in the future.

Some of the new retworkx code has been upstreamed, other bits are in the process of being upstreamed. This PR works with my feat-balanced-cut-edges branch here: https://github.com/InnovativeInventor/retworkx/tree/feat-balanced-cut-edges.

[InnovativeInventor]

The speedup should be > 16x now, for some computers at least.