GitLab

* [Fix] fix some warnings in unittest

* [Impl] standardize some warnings

* [Fix] fix warning type in test_deprecation

* [Fix] fix warning type

* [Fix] continue fixing

* [Fix] fix some details

* [Fix] fix docstring

* [Fix] del useless statement

* [Fix] keep compatibility for torch < 1.5.0

* [Docs] Add header for files

* change to OpenMMLab

* add headers for .cpp, .cu, .h, .cuh

* replace Open-MMLab with OpenMMLab

* add copyright header

* change # to // for cpp files

* add yapf and isort to travis

* minor formatting

* remove blank lines

* skip unit tests for progressbar when python2

* update travis to ubuntu 16.04

* use a newer version ffmpeg

* add -y to add-apt-repository