Client API need be refactored and enhanced

[foreverneverer]

Now the Java client API has follow problem:

• redundant: it contain such as batchGet, batchGet2, batchMultiGet and so on, we expect it can be simply and clear
• deficient: it just offer based set/get/del, but no auto-retry, auto-compressed, we expect it can have more auto function.
• no support server-duplication: the latest Pegasus-Server offer duplication cluster, but the client can't support visit two cluster meanwhile.

Potential Roadmap:

• Simply API refactor and simplify the API #122 refactor: simplify api using encapsulating parameters and results #124

• Support auto-compress support option to enable compression and hide details of compression from users #123 feat: using "interceptor" to enhance the api(compress) #126

• Refactor backup-request using interceptor support option to enable compression and hide details of compression from users #123 refactor: using "interceptor" to implement backup-request #125

• Support auto-retry

• Support RateLimiter

• Support auto-serialize

• Support dualClient to connect two cluster