(cherry picked from commit 8600bf0)

* fixed unit tests to support phpunit 6

* do not use sudo

* update elasticsearch in the travis env and use docker vm

* add java jdk8

* temporary remove elasticsearch scripting

* clean up travis file

* null cannot be used in count() functions anymore in 7.2

* remove deprecated queries

* move tests

* added support for 5.x elasticsearch syntax

changed script_score lang to painless

* refactored tests to support elastic 5

* update changelog

* uri parameters was moved to container, introduced 5.0 new request body parameters

* removed filter endpoint, change order for query and postfilter

* search test has too many not necessary test cases

All those tests has to be in specific query or endpoint. Also functional tests make more sense then asserting it in the SearchTest

* moving elasticsearch/elasticsearch to required dependencies