* [tvm4j] RPC Server
* [tvm4j] fix recursively function calling; connect to proxy server; osx rename .so to .dylib
* [tvm4j] test case for proxy connection; thread pool for serving
* [tvm4j] register user-defined function
* [tvm4j] define java function (pushArgToStack) to convert arguments to C TVMValue
* [tvm4j] make Module & Function extends TVMValue
* [tvm4j] make registered cb function return Object
* [tvm4j] add cb finalizer; add TVMValueBytes
* [tvm4j] support NDArrayBase cb arg
* [tvm4j] register cb function unit tests
* [tvm4j] pass Function.Callback to resource_handle
* [tvm4j] fix type cast