Adding missing methods that were left out of https://github.com/addthis/hydra/pull/6
Merge branch 'master' of https://github.com/addthis/hydra

Conflicts:
	hydra-data/src/main/java/com/addthis/hydra/data/tree/ConcurrentTree.java
	hydra-data/src/main/java/com/addthis/hydra/data/tree/ConcurrentTreeNode.java
	hydra-data/src/main/java/com/addthis/hydra/data/tree/ReadTreeNode.java
	hydra-data/src/main/java/com/addthis/hydra/data/tree/TreeNode.java