closes #11
service startup check added
better shutdown signal handling.
Merge pull request #12 from CERT-Polska/issue-12

https://github.com/CERT-Polska/hsn2-swf-cve/issues/4
add attribute name to logs
Some connectors tests implemented.
Merge branch 'code-cleaning' into develop
Merge branch 'develop' of https://github.com/CERT-Polska/hsn2-commons-java into develop
POM fix.
Tests bug fix.
Remove usage of protobuf serialization in DataStore.
Tests implementation, in progress.
DataStore connector tests added.