HH-34878: supervisor: stop stale workers on `stop`, report stale workers on `status`, tune timeouts for `stop`
HH-34878 on start -- wait for all workers to start serving, on stop -- tune timeout for sigkill
HH-34942 fix init-script exit codes to be more complying to LSB
Merge remote-tracking branch 'origin/HH-34878' into release-candidate
Merge remote-tracking branch 'origin/HH-34942' into release-candidate
HH-35783 - Added log_blocked_ioloop_timeout setting
Merge remote-tracking branch 'origin/HH-35783' into release-candidate
release 0.6.2