Agent should not kill a quiet task being this task the only one running

Current behavior

• Universal Agent may kill a task due to an oversleeped heartbeat event.
• The probability may be one out of 1000 or 10000 heartbeats, i.e about once in 10 hours,
• especially if the task runs quiet and is the only one.

Desired behavior

• The Agent should answer with a heartbeat to Master should no other HTTP operation on behalf of the Master be executed.