In preparation for moving to Elastic's CI (#862)

* In preperation for moving to Elastic's CI

Add dockerfile to build image for testing python client in a docker container
add docker-compose to create environment for running tests against specific versions of ES
Add Makefile to make it easy to execute tests and cleanup
add wait-for-elasticsearch.sh script to wait for elasticsearch before executing the tests.

* add pull and comment about pushing requring auth

* spelling errors

* adding CI directory for jenkins to pick up

fixing typo too

* fix test-matrix and create working run-tests

* add comment about why skipping python 2.6

* adding dockerfiles to create base images for ci

docker-compose.yml

@@ -0,0 +1,36 @@
+version: '3.3'
+services:
+  client:
+    image: docker.elastic.co/clients/elasticsearch-py:${PYTHON_VERSION:-3}
+    build:
+      context: .
+      dockerfile: Dockerfile
+      args:
+          PYTHON_VERSION: ${PYTHON_VERSION:-3}
+    environment:
+      - "TEST_ES_SERVER=http://elasticsearch:9200"
+    volumes:
+      - .:/code/elasticsearch-py
+      - esvol:/tmp
+    networks:
+      - esnet
+    depends_on:
+      - elasticsearch
+    command: ["true"]  # dummy command to override the command in the Dockerfile and do nothing.
+  elasticsearch:
+    image: docker.elastic.co/elasticsearch/elasticsearch-oss:${ELASTIC_VERSION:-6.2.4}
+    volumes:
+      - esvol:/tmp
+    networks:
+      - esnet
+    environment:
+      - path.repo=/tmp
+      - "repositories.url.allowed_urls=http://*"
+      - node.attr.testattr=test
+      - bootstrap.memory_lock=false
+      - "discovery.zen.ping.unicast.hosts=elasticsearch"
+      - "http.max_content_length=5mb"
+networks:
+  esnet:
+volumes:
+  esvol: