Execute Action at monitoring server failure.(deal with Issu 251)

Add a mechanism to do the action, when detected of the monitoring server failure (e.g. doesn't reply).

When Arm thread initializ, register trriger and monitoring server info to chashDB(sqlite).
when a failure was detected, Update the trigger and Register the event, and to perform the action(if registration).
TriggerID / Message Comment is a provisional value.

please confirm and comment.
Please confirm, these IDs are not used by Zabbix from the Zabbix's source code.
For example, Zabbix's Node ID is realized with higher bit of Host ID.