change imports to coreos/etcd coreos/go-raft; change API to work with new go-raft
Merge pull request #1 from xiangli-cmu/master

Change imports to coreos/etcd coreos/go-raft
add testAndSet Command
Merge https://github.com/coreos/etcd
register new commands
Merge pull request #2 from xiangli-cmu/master

Add testAndSet Command
clean tree struct code
Merge pull request #3 from xiangli-cmu/master

clean up tree.go
add [etcd] as the prefix of the logging info
Merge pull request #4 from xiangli-cmu/master

add [etcd] as the prefix of the logging info
clean up tree.go and watcher.go
Merge pull request #5 from xiangli-cmu/master

clean up tree.go and watcher.go
some defaults