Log Message:
logswan: update to 2.1.13.

Logswan 2.1.13 (2022-07-28)

- Remove useless backslashes in usage()
- Add entries with IPv6 remote hosts to exercise the IPv6 code paths
- Add an invalid.log log file with invalid lines, for testing purposes
- Add a few more test cases in CMakeLists.txt
- Also generate data for IPv6 addresses in the MMDB test database
- Regenerate the example MMDB database and JSON example output