It's difficult to know if a release process is running too long when
we don't have a history of how long it should run for.
This is mostly the stats function from run_all.sh that has been
sending stats about runtimes there. Wrap it in a vos_release function
with some minor refactoring, and update the scripts.
As noted inline, there's already release timer stats going to
afs.release.<volume> for the periodic release of docs/tarballs etc.
Change-Id: I3d79d1a0997af8977050b7f6e7cf3b7578cc8491
339cbf4c3d