Add terminated flag to agent context + as optional in state update msg + send...

Add terminated flag to agent context + as optional in state update msg + send on EcsCoreAgent terminate

- Add terminated flag in agent context, default False + accessor
- Add optional flag to state update message, default False
- Improve logic of state update message print method
- Add corresponding optional flags in state publish methods in StareCoreAgent
- Broadcast state update with terminated flag set before starting to close sockets in EcsCoreAgent