ZOOKEEPER-1718. Support JLine 2 (Manikumar Reddy via phunt)

git-svn-id: https://svn.apache.org/repos/asf/zookeeper/trunk@1528219 13f79535-47bb-0310-9956-ffa450edef68
ZOOKEEPER-1655. Make jline dependency optional in maven pom (Thomas Weise via phunt)

git-svn-id: https://svn.apache.org/repos/asf/zookeeper/trunk@1528224 13f79535-47bb-0310-9956-ffa450edef68
ZOOKEEPER-1770. NullPointerException in SnapshotFormatter (Germán Blanco via phunt)

git-svn-id: https://svn.apache.org/repos/asf/zookeeper/trunk@1528271 13f79535-47bb-0310-9956-ffa450edef68