Investigate if/how to integrate Saturn into HEIR

[AlexanderViand-Intel]

Saturn is a introduced in "Level Aware Bootstrapping Placement for Fully Homomorphic Encryption Using MaxSAT", a MSc thesis by William Seo from CMU, supervised by Wenting Zheng and Fraser Brown.

On average Saturn achieves a 5.25× speedup in bootstrapping placement
selection time compared to DaCapo [7], the state-of-the-art automatic bootstrapping method.
Additionally, the benchmarks generally have faster estimated inference time for a CIFAR-10
image, when bootstrapped by Saturn versus when bootstrapped by DaCapo [7].

[j2kun]

FWIW, it appears that OR-tools has a MAX-SAT solver, so this may be easy to replicate: https://github.com/google/or-tools/blob/8edc858e5cbe8902801d846899dc0de9be748b2c/ortools/sat/sat_parameters.proto#L701