Kafka Plugin for Graylog

This is an Graylog input plugin to add the support of newer kafka version like 1.1.0.

This is fully a plugin portage of the work of @muralibasani on this PR: Graylog2/graylog2-server#4770

This plugin is here waiting a merge or improvement on Graylog of kafka support

Required Graylog version: 2.4.0 and later