Openmmlab backup

[davidpagnon]

Mostly fixes #75. All high-level solutions and example work.
However, some models from the model zoo are still missing:

MISSING MODELS:

RTMPose HALPE26:
- rtmpose-l_simcc-body7_pt-body7-halpe26_700e-256x192-2abb7558_20230605
- rtmpose-t_simcc-body7_pt-body7-halpe26_700e-256x192-6020f8a6_20230605

RTMPose COCO17:
- rtmpose-l_simcc-body7_pt-body7_420e-384x288-3f5a1437_20230504

RTMPose COCO133:
- rtmpose-l_simcc-ucoco_dw-ucoco_270e-256x192-4d6dfc62_20230728
- rtmpose-l_simcc-ucoco_dw-ucoco_270e-384x288-2438fd99_20230728
- rtmpose-s_simcc-ucoco_dw-ucoco_270e-256x192-3fd922c8_20230728
- rtmpose-t_simcc-ucoco_dw-ucoco_270e-256x192-dcf277bf_20230728

RTMPose Face:
- rtmpose-m_simcc-face6_pt-in1k_120e-256x256-72a37400_20230529
- rtmpose-s_simcc-face6_pt-in1k_120e-256x256-d779fdef_20230529
- rtmpose-t_simcc-face6_pt-in1k_120e-256x256-df79d9a5_20230529

YOLOX (including animal classes):
- yolox_l_8xb8-300e_humanart-ce1d7a62

Also, I realize I did not create another branch, and this pull request is also included: #70
Tell me if you want me to separate them out!

[davidpagnon]

No need anymore as the servers are back on: #75 (comment)