bump version to 1.2.9
bump version to 1.2.9

[ci skip]

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