[tests] review of all our integration tests

[degemer]

@hkaj :

• btrfs.py
• fluentd.py - [tests] Improve tests for fluentd check. #1574
• lighttpd.py - [tests] switch lighttpd check to AgentCheckTest. #1473
• mesos_slave.py
• network.py
• nginx.py
• redisdb.py
• sqlserver.py
• tcp_check.py

@LeoCavaille :

• cacti.py
• couchbase.py
• jenkins.py
• kafka_consumer.py
• mesos.py
• mongo.py
• ntp.py
• postfix.py
• rabbitmq.py - [rabbitmq] Improve test suite and fix tagging #1472
• riakcs.py
• varnish.py

@degemer :

• couch.py - [tests] use AgentCheckTest for couch.py #1462
• go_expvar.py - [go_expvar] use AgentCheckTest & add CI #1491
• haproxy.py - [haproxy] use new test class #1466
• http_check.py - [http_check] add coverage_report #1467
• postgres.py - [postgres] Collect StatIO per table & revamp test #1415 (thanks @LeoCavaille)
• process.py - [process] clean check & test #1470
• riak.py - [riak] add integration test #1499
• system_core.py - [system_core] Add AgentCheckTest mocked test #1485
• vsphere.py - it's a WON'T FIX for now
• win32_event_log.py

@remh :

• elastic.py - [ElasticSearch] Improve tests and bug fixes #1487
• etcd.py
• gearmand.py- [Gearman] Improve integration #1476
• gunicorn.py
• hdfs.py
• kyototycoon.py
• mcache.py - [Memcache] Improve tests and bug fixes #1490
• ssh_check.py
• teamcity.py
• tokumx.py

@yannmh :

• docker.py
• marathon.py
• activemq_xml.py - [activemq] enable ci + tests ✅ #1606
• apache.py - [apache] review tests #1474
• directory.py - [directory] add tests #1463
• iis.py - [iis] review tests #1484
• mysql.py - [mysql] rewrite tests #1471
• nagios.py - [nagios] review tests #1493
• snmp.py - [snmp] review tests #1477
• supervisord.py - [supervisord] selct processes by regexp name match #1747
• windows_service.py- [windows_service] refresh check and add tests #1481
• wmi_check.py - [wmi] add tests #1502
• zk.py - [zk] CI + tests #1488

[remh]

Won't be completed by 5.3.0 let's finish this for 5.4.0

[yannmh]

Moving to 5.5.0

[degemer]

Not finished, but the initial goal is attained: way more checks have integration tests than before.
Closing, checks are now in https://github.com/DataDog/integrations-core.