rr 5.9.0 released

[Robert O'Callahan]

There are lots of small but valuable fixes in this release, as usual, but the main visible improvement in this release is that on Linux kernels >= 6.10, rr works with `perf_event_paranoid` = 2, which is usually the default.

I made the release because we're planning to make some changes that might be a bit destabilising.

Rob

--

Su ot deraeppa sah dna Rehtaf eht htiw saw hcihw, efil lanrete eht uoy ot mialcorp ew dna, ti ot yfitset dna ti nees evah ew; deraeppa efil eht. Efil fo Drow eht gninrecnoc mialcorp ew siht - dehcuot evah sdnah ruo dna ta dekool evah ew hcihw, seye ruo htiw nees evah ew hcihw, draeh evah ew hcihw, gninnigeb eht morf saw hcihw taht.