Fix for issue #294 and other clean-ups related to ZK installation

Changes in prep for ZK rolling restart implementation include:
- Fix for issue #294.
- Changes for enhancement #309 
- Changes to prevent manual change to the zookeeper data directory by an admin. But changing the data dir through chef attributes will not be prevented since the directory gets created before the ZK start.
- Stop [ZK init](https://github.com/bloomberg/chef-bcpc/blob/4c4ba33f0106468f287470e29e624be3b163326c/cookbooks/bcpc-hadoop/recipes/zookeeper_server.rb#L53-L56) and [update-alternatives](https://github.com/bloomberg/chef-bcpc/blob/4c4ba33f0106468f287470e29e624be3b163326c/cookbooks/bcpc-hadoop/recipes/zookeeper_config.rb#L12-L17) resources after the first run.