add clock synchronization feature (NTP)

[dudekw]

Laser scanner (LMS100) is capable of clock synchronization (using Network Time Protocol). This PR:

1. adds clock synchronization to the LMS1xx library.
   • Scan data structure returns:
     • time stamp of the msg - seconds,
     • time stamp of the msg - micro seconds,
     • time since laser scanner start up - micro seconds
   • An additional configuration method is implemented.
2. adds configuration parameters to the launch file,
3. adds the LMS1xx_NTP_diagnostic node to print current state of the laser scanner,
4. modifies the LMS1xx_node node to handle the NTP clock synchronization (if the useNTP param is set true)