Cf

• Correctly rewrite bounded repetitions following an explicit class uap-rust#29 (significant reduction in memory consumption of the rust impl)
• Use an atom length of 2 for the regex filtering uap-rust#31/Re2 bench updates, revert #31 for UAs and OS uap-rust#32 (very significant perf improvement of the devices matcher with atoms of size 2)
• Investigate updating the re2 matcher to use an atom length of 2 #263 (can't tune atoms size in re2)

Meaning the memory overhead should be dramatically lower than it used to and competitive with re2, and the performance should be even better comparatively.