Suppress NodeExists log message

When invoking invoking Curator's creatingParentsIfNeeded node builder,
if the parent does not exist the following is logged at INFO level:

14:28:40,189  INFO ProcessThread(sid:0 cport:-1): server.PrepRequestProcessor:645
Got user-level KeeperException when processing sessionid:0x14523b328600000
type:create cxid:0x5 zxid:0x5 txntype:-1 reqpath:n/a Error Path:/xd/streams
Error:KeeperErrorCode = NodeExists for /xd/streams

This is harmless but very confusing for people reading the logs.
The modifications to the log4j.properties in this commit will
suppress INFO level messages from this ZooKeeper class.
Provided names for PathChildrenCache threads

When reading a thread dump or stack trace generated
by a PathChildrenCache thread it is helpful to
know which cache that thread is serving. This
change provides a meaningful name to the thread
Curator creates for these caches.

Also introduced an AtomicReference for the containers
cache. The idea is that the reference isn't set
until the cache is started and the reference is
removed before the cache is closed.
Fix NoNodeException in AbstractControllerIntegrationTest

- Suppress org.apache.zookeeper.KeeperException when repositories reset
Speedup build process

- Support tests to run in parallel
  - Fix some of the tests so that they can run in parallel.
  - Configure maxParallelForks to use available core
  - Increase forkEvery value for spring-xd-dirt tests and for the rest of the tests.
- Modify jvm args for compile and test