* Add kibana5 and logstash5
* Upgrade the elastic beats to 5.4
* Make sure all elastic products use the same version
(see elk5Version)
* Add a test for the ELK stack
Note: the option to configure the watchdog timeout seems to be gone
in the 2.3 series of Logstash. It complains about an unknown option
and it is not in the source anymore. I am thus removing this
configuration option to adjust the service to these changes, too.
with the last commit for logstash plugin the bin path was not being used and the executables
were written directly in the root directory
this results in the failure of the logstash service configuration.
additionally the logstash tool itself does not start because it cannot source shell libraries relative
to the current location