Remove Apache Maven repo because Storm and Kafka are in Maven Central
Force use of IPv4 instead of IPv6 (-Djava.net.preferIPv4Stack=true)

Notably, this prevents tests to fail on Mac OS X because of timeouts caused
by resolution of localhost and IPv6.  Storm uses a hardcoded test timeout of
5 seconds (see `TEST-TIMEOUT-MS` in `backtype.storm.testing.clj`), which is
often exceeded because of the long duration of resolution on Mac OS X
when IPv6 is enabled.

For more details on the timeout issue see:
https://issues.apache.org/jira/browse/STORM-70
https://issues.apache.org/jira/browse/ZOOKEEPER-1476
Use Storm 0.9.2
ZooKeeperEmbedded: set default port to 2181
Explain that upcoming ZK 3.5.0 will provide better controls to configure JMX
Explicitly define return type of connectString
Expose hostname and port of ZooKeeperEmbedded
zkclient: exclude ZooKeeper dependency
KafkaEmbedded: use randomized local log.dirs, and remove it on shutdown
KafkaSpec: use random ZK port
KafkaStormSpec: use random ZK port
Remove redundant time unit information from log messages
KafkaStormSpec: use before/afterEach instead of before/afterAll
log4j.properties (tests): squelch distracting log messages
Move implicit Injection (Bijection) higher up as it's more like an import
Remove setting STORM_LOCAL_MODE_ZMQ because it is already set correctly by default
Explain how to tell Storm 0.9.3+ to use a different ZK instance for testing
Reorder imports
Simplify expression
Auto-format code