[2014/11/14] 1.2.0 release

feature updates
- Added storage access time watching feature
- Replication over cluster

bug fixes
- Avoid to close the already closed socket.
- Fix bwlimit when creating new partition
- Fix initial value of epoll socket
- Fix pthread_cond_wait() in zookeeper_lock::_assure_session_connected()
- Fix resource leak of server socket
- Fix some initialization
- Fix the race condition in thread class
- Fix zookeeper_lock::_assure_session_connected()
- Fixed socket condition add_epoll_socket and add_kqueue_socket
- Modified include guards to fit them to the C++ standard naming convention.
- Skip proxy when destination node is down

others
- Support TravisCI