Merge branch 'master' into gen_proofmode

also improve README
4 jobs for gen_proofmode in 38 minutes and 29 seconds (queued for 1 minute and 46 seconds)
Status Job ID Name Coverage
  Build
passed #13564
fp
build-coq.8.7.1

00:06:35

passed #13563
fp-timing
build-coq.8.7.2

00:05:21

passed #13562
fp-timing
build-coq.8.8.0

00:04:32

passed #13561
fp
build-coq.dev

00:28:34