Log Message:
logswan: update to 2.1.8.

Logswan 2.1.8 (2020-10-19)

- Make displayUsage() static
- Removing some leading whitespace characters
- Constify methods and protocols names array
- Constify countries and continents names and ID arrays
- Enable FORTIFY_SOURCE level 2
- Call memset() to set all entry_data struct fields to zero