Provide service call to verify time synchronization status

[boxanm]

Currently, the ROS driver contains a service call to set up different time synchronization methods (ntp, ptp, GPS). However, it is not possible to read the master-slave device delays and, therefore, assess the synchronization quality. Devices from other brands usually provide some status, for example "locked", together with the delay in ticks or nanoseconds between the two devices.

Since the Windows app allows us to check the status, I assume the packets must contain these values, and it is simply a question of writing the appropriate service call to read and interpret these values. Nevertheless, since most ROS systems, including ours, are running on Linux, using the Windows app is not an option.