Closes #2 Replacing all references to ZooKeeper with CuratorFramework wh...

...ere possible.
While we're trying to minimize the impact of Accumulo classes changing beneath us, I think this may be a good candidate. It's not something I would expect to change, but it IS another dependency nonetheless. One case I could see against us copying these classes, however, is when a bug is found in Accumulo- we'll need to fix it in both places.