[New Configs] Add new config file for ade20k and maskformer

[tackhwa]

• The Configs file had been tested, all the training can be run properly and the inference result is same as result in this link

• Training for maskformer_r50_d32_8xb2_160k_ade20k_512x512.py

• Training for maskformer_r101_d32_8xb2_160k_ade20k_512x512.py

• Training for maskformer_swin_s_upernet_8xb2_160k_ade20k_512x512.py

• Training for maskformer_swin_t_upernet_8xb2_160k_ade20k_512x512.py

• Inference result of maskformer_r50_d32_8xb2_160k_ade20k_512x512.py

• Inference result of maskformer_r101_d32_8xb2_160k_ade20k_512x512.py

• Inference result of maskformer_swin_s_upernet_8xb2_160k_ade20k_512x512.py

• Inference result of maskformer_swin_t_upernet_8xb2_160k_ade20k_512x512.py