Change list

Timeouts mechanism overhaul:
- Removed soft_timeout/hard_timeout configurations in favor of just timeout
- Removed critical_timeout in favor of a defaulted grace_period. The rationale was that nobody understood what is the meaning of "critical" timeout. The idea of the critical timeout was to allow the last resort option of killing the worker in cases where SIGTERM did not succeed. I find grace_period to be more convenient and intuitive.

Breaking Changes:

Sergeant Timeouts config does not provide soft_timeout, hard_timeout and critical_timeout anymore. They were replaced with timeout and grace_period