Removes events for the next step of the distributed simulation (with time stamp
smaller than the safe time from the server) from the temporary calendar and
puts them to the final calendar.
Sends Error message to all submodels, informing them about falling down of a specified
submodel and carries out appropriate actions related to that error.
His wait() and notify() methods are used to wait for message
from server indicating that all submodels have finished
current step of the distributes simulation.