* Modify data download function, and support unittests of inference APIs on windows, test=develop

* The import error compatible with py2 and py3, and fix unittests problems of inference APIs on Windows, test=develop

* Add mkldnn bfloat16 option to C-API

* Add test for bfloat16 gpu

* Change coverage test

* Repair capi_gpu test

This reverts commit 02083bda.

* Add mkldnn bfloat16 option to C-API

* Add test for bfloat16 gpu

* Change coverage test

* fix inference c api lod, test=develop

* fix capi lod problem and enrich tests, test=develop

* delete useless header files and alter const_cast, test=develop

* support  golang inference

* fix the CAPI ZeroCopy shape error and reconstruct the output obtain

* use an anonymous namespace to cover the functor

* fix unit tests because of the output of typeid(T).name() is different from linux and windows, test=develop

* fix the PD_ZeroCopyPredictorRun output problem and add some checks and logs for users

* modify the cmakelists depends and fix the cmakelists problem

* add capi for fluid inference api, including AnalysisConfig, AnalysisPredictor, PaddleBuf, PaddleTensor, ZeroCopyTensor