GitLab

* add 1_exist_data_model.md chinese version

* add 1_exist_data_model.md chinese version

* add 1_exist_data_model.md chinese version

* add 1_exist_data_model.md chinese version

* add 1_exist_data_model.md chinese version & modify 1_exist_data_model.md english version

* add 1_exist_data_model.md chinese version & modify 1_exist_data_model.md english version

* add 1_exist_data_model.md chinese version & modify 1_exist_data_model.md english version

* add 1_exist_data_model.md chinese version & modify 1_exist_data_model.md english version

* add useful_tools.md chinese version

* typo fix

* Merge branch 'master' of github.com:open-mmlab/mmdetection3d into add_useful_tools_cn

* Revert "Merge branch 'master' of github.com:open-mmlab/mmdetection3d into add_useful_tools_cn"

This reverts commit 90de7b67fbb63fa5c6ca162b53356e02250f1892.

* fix typo

* typo fix

* typo fix

* Update index.rst

* Create s3dis_sem_seg.md

* Create scannet_sem_seg.md

* Update index.rst

* [Docs] Chinese Document of faq

* Deprecated pycocotools faq

* refine doc

* refine numba doc

* add demo.md chinese version

* add demo.md chinese version

* add demo.md chinese version

* add demo.md chinese version

* Chinese document structure alignment

* fix typos in compatibility.md

* fix version of sphinx

* fix switch

* Add mmseg in the doc config files

* Remove mocked cv2

* Add opencv-python

* Remove mocked imports

* Add mminstall requirements

* Remove mocked imports correspondingly

* Fix mmdet versions

* Fix mmseg version

* add chinese doc

* update