Merge branch 'stable-3.6' into stable-3.7
* stable-3.6:
Register Kafka consumers with external groupId when plugin starts
Make KafkaBrokerApi class implement ExtendedBrokerApi interface
Consume events-broker from source
Add validation dependency on events-broker module
Add .gitignore file in the project
Pass correct amount of arguments to Malformed event log line
Add Kafka REST API authentication
Fix the topic events replay Kafka REST-API
Use Kafka REST Proxy id to subscribe to the correct instance
Fix Kafka REST Proxy accepts header for topic meta-data
Kafka REST Client: avoid clashes between clients
Fix threshold of HTTP wire logging
Delete subscription at the end of ReceiverJob
Update kafka-client 2.1.0 -> 2.1.1
Increase patience to 30s for shouldReplayAllEvents test
Remove unused RequestConfigProvider
REST ClientType: Make thread pool and timeouts configuration
Extract configuration properties into constants
Manage Kafka clientType when starting session
Receive messages through Kafka REST API
Send messages through Kafka REST API
Abstract Publisher/Subscriber into generic interfaces
Wait at most for 5s for an empty topic
Assert that messages are acknowledged in KafkaBrokerApiTest
Add Kafka REST-API container in test
Remove access to deprecated poll(long) method
Use explicit Kafka image:tag in tests
Do not connect KafkaSession without bootstrap servers
Change-Id: Icd9e8f52e97fa18662350b3508dd57c35d5db753