Updated docu:fixed screenshot links
Updated docu:fixed screenshot links

frankscholten/logstash,alex-glv/logstash,kensipe/logstash,frankscholten/logstash,suppandi/logstash,mesos/logstash,suppandi/logstash,frankscholten/logstash,kensipe/logstash,frankscholten/logstash,mesos/logstash,mesosphere/logstash,alex-glv/logstash,kensipe/logstash,alex-glv/logstash,mesosphere/logstash,suppandi/logstash,kensipe/logstash,suppandi/logstash,mesosphere/logstash,mesosphere/logstash,alex-glv/logstash