[WIP] tensorboard-notf for pytorch

[lanpa]

This modification let pytorch/pytorch@00b8330 use the code inside tensorboard installed by whl file build by bazel.

The generated event file can be rendered correctly by web server build from:
#1663

TODO:

• rename tensorboardX to something else (keep this name to avoid namespace confusion)
• correct way to handle plugin protos (now copy that directly)
• unittests
• fill license information to pass the test
  cc @orionr @nfelt