BUG 408

- added null safe comparison
- added unit test
- added SLF4j
- added log message in method StrIpToIntIp in case of exception

Change-Id: Id15dc4f80d419df5e73ab79fea4e8ab25ec82968
Signed-off-by: Michal Rehak <mirehak@cisco.com>
Merge "BUG 408"