feat(core): closed states instead of lost states (#573)
feat(core): closed states instead of lost states (#573)

In order to be better in sync with the official documentation (https://zookeeper.apache.org/doc/r3.5.5/zookeeperProgrammers.html#ch_zkSessions) it is better to rename those variables to `close` instead of `lost`.
python-zk/kazoo,python-zk/kazoo