start services with docker-compose

[graphaelli]

Adds scripts/compose.py, a utility for generating a docker-compose.yml useful for development and integration environments, and use it for integration tests under CI.

replaces #75

[graphaelli]

Version tests pass on my machine but not on jenkins due to the max path length (BINPRM_BUF_SIZE of 127) being exceeded under jenkins - /var/lib/jenkins/workspace/elastic+apm-integration-testing+master+multijob-python-agent-versions/APM_SERVER/master/PYTHON_AGENT/github/bin/python. We'll have to figure that out before merging this.

[jalvz]

this still doesn't work for me, i only made work it once and never again :(

the issue is always a timeout on querying ES

retry.py                   200 DEBUG    Converted retries value: False -> Retry(total=False, connect=None, read=None, redirect=0, status=None)
connectionpool.py          396 DEBUG    http://localhost:9200 "GET /apm-*/_count HTTP/1.1" 200 71
base.py                     83 INFO     GET http://localhost:9200/apm-*/_count [status:200 request:0.003s]
base.py                     85 DEBUG    > {"query": {"bool": {"must": [{"term": {"processor.event": {"value": "transaction"}}}]}}}
base.py                     86 DEBUG    < {"count":0,"_shards":{"total":0,"successful":0,"skipped":0,"failed":0}}

will have to spend some time tracking it down but would appreciate some help to see what i'm doing wrong

[graphaelli]

there's an issue with the current snapshots - let's rerun when something newer than jun-1 is available.

[graphaelli]

failing on ci until container image with elastic/apm-server#986 is built