Fix memory leak in #get_acl().
Fix memory leak in #get_acl().

songling88/zookeeper,songling88/zookeeper,rickypai/zookeeper,zk-ruby/zookeeper,songling88/zookeeper,rickypai/zookeeper,songling88/zookeeper,zk-ruby/zookeeper,zk-ruby/zookeeper,rickypai/zookeeper,rickypai/zookeeper