Livongo fork of Kafka

We are maintaining a fork of kafka in order to have a RocksDBTTL Topic cache. We tried to get this merged upstream without success: https://issues.apache.org/jira/browse/KAFKA-4212

First bootstrap and download the wrapper

cd kafka_source_dir
gradle

publishing a new livongo version

git pull from kafka upstream
add upstream commits onto Livonogo trunk
compile & run tests (see kafka main README)
update gradle.properties's version field to add -LIVONGO suffix
update gradle.properties's mavenUrl field
update gradle.properties's mavenUsername field
update gradle.properties's mavenPassword field
run ./gradlew uploadArchivesAll to upload new jars to Livongo artifactory