Supporting v6.8.2

Merge pull request outbrain-inc#21 from outbrain/v7.4.0

Adding support for 7.4.0

Bumped version to 5.5.1

Updating v5.4.1

Bumped to version 5.5.0

Release for kibana 5.3.0

Release for kibana 5.2.2

4.0.0

adding binary for releases