GitLab

* Add new test ID and test env info to the benchmark run.

* Fix test.

* Fix lint

* Address review comment.

* Exemplify csv handing in serving for boosted_trees model by using custom built signature_def.

* some minor touches.

* Reverted back to using the file instead of module in the example.

* Make boosted_trees Garden-official

* Fix nits

* Add boosted_trees to the official models

* Comments addressed from review, and a test added; using absl.flags instead of argparser.

* Used help_wrap. Also added instructions for inference.