v0.68.0

This release includes cgroups support for CPU and memory limits, a new feature that requires a Mesos agent configuration change and ensures a misbehaving task won't block the whole FLP.

• Resource limits:
  • [core] Support Mesos task resource limits specification for task classes
  • [core] Prevent crash in incomplete limits
  • [core] Print limits to IL
  • [core] Avoid triggering dead or inactive hooks on teardown
  • [core] Proceed with task kill even if some cannot be killed
  • [core] Explicit handling of executor/agent failed events
  • [core] Only perform a STOP transition for ACTIVE tasks
  • [core] Wait for 500ms for ERROR states to settle before GO_ERROR/STOP