Add version.py.

* Add license to the top of files

* Add licenses agreement on the demo files

* Add C++ and python style check to travis.  
* Update all C++/python code that violate coding standards.

* change paths

* add setup

* add packages

* update

* install ready

* restore mock

* restore graph_test.sh

* move visualdl.py to visualdl as a script

* fix setup

* remove onnx_pb2.py

* fix server_test

* add package into tests.sh

* add protobuf-compiler for package

* recover .git

* change script bin visualdl_bin to visualDL

* add npm cache

* avoid build_frontend in travis-CI

* avoid frontend build in travis-CI

* add pips

* restore protobuf mannul installation

* install protobuf

* fix package

* fix tool

* init logdir runs tags and scalars interface

* add debug

* add one mock data

* add dir server

* move frontend to server

* optimizer python package

* add mock data

* add back result encode

* use application/json as Response type

* rm .DS_Store

* update mock tags

* update mock data