FEATURE : Use apache dynamic urls service instead of static url.

In this pull request, I get download urls of ZooKeeper from `http://www.apache.org/dyn/closer.cgi/zookeeper/` . Using the official web page suggest the fastest url is better than static url. In some country like China, I almost access the `tds.net` cause the network delay or other reason.
And I suggest use blank space instead of tab cause the indent problem.
Set the same version of zk at different platform.