OPTIMIZATION

1. Stream:
Starting de-serialization while receiving the Memcached response instead of waiting for the entire response to come back.
2. Java direct buffer:
Reduce unnecessary object creation and Java garbage collection.
3. Native serialization:
Optimized some of the serialization strategy, and support customized object transcoder.
4. Re-implement connection pool:
Simplify the connection pool maintain strategy and create the connection dynamically.
5. New Features:
Add memcached binary and UDP protocol support
6. Source code refinement and tuning:
Refined nearly all the source code of Whalin to help increase the performance.