Add health diagnostics of the device via statuses, alarms, and log entries

This adds health diagnostics of the device via statuses, alarms and log entries. To do this, the connection and closing of input channels are monitored and corresponded entries are sent in the log.

In order to increase robustness, data from XGM is optional now. If the channel is closed, fake values are substituted. This state is reported by raising warning via alarm system and corresponded entry in the log.

Input from Timeserver (BunchPattern) is crucial. The device cannot proceed without this information, and sends no data to output channel. This state is reported by changing device state in UNKNOWN, raising alarm via alarm system and corresponded entry in the log.

Closes #8 (closed) Also concerns #7 (closed)