GitLab

Update some lint rules, including:
* change max line length from 79 to 120, following [pytorch]
* add dedent_closing_brackets in yapf
* remove typed def requirements in mypy

Fix return code bug in setup.py, when lint/test command return 1,
`os.system` will return 256 and `sys.exit(256)` will get return code 0.

[pytorch]: https://github.com/pytorch/pytorch/blob/d1dcd5f/.flake8#L3