## Motivation
Make MMSeginferencer easier to be used
## Modification
1. Add `_load_weights_to_model` to MMSeginferencer, it is for get
`dataset_meta` from ckpt
2. Modify and remove some parameters of `__call__`, `visualization` and
`postprocess`
3. Add function of save seg mask, remove dump pkl.
4. Refine docstring of MMSeginferencer and SegLocalVisualizer
5. Add the user documentation of MMSeginferencer
## BC-breaking (Optional)
yes, remove some parameters, we need to discuss whether keep them with
deprecated waring or just remove them as the MMSeginferencer just merged
in mmseg a few days.
Co-authored-by: xiexinch <xiexinch@outlook.com>
## Motivation
Support `MMSegInferencer` for providing an easy and clean interface for
single or multiple images inferencing.
Ref: https://github.com/open-mmlab/mmengine/pull/773https://github.com/open-mmlab/mmocr/pull/1608
## Modification
- mmseg/apis/mmseg_inferencer.py
- mmseg/visualization/local_visualizer.py
- demo/image_demo_with_inferencer.py
## Use cases (Optional)
Based on https://github.com/open-mmlab/mmengine/tree/inference
Add a new image inference demo with `MMSegInferencer`
- demo/image_demo_with_inferencer.py
```shell
python demo/image_demo_with_inferencer.py demo/demo.png fcn_r50-d8_4xb2-40k_cityscapes-512x1024
```
---------
Co-authored-by: MeowZheng <meowzheng@outlook.com>
Miao Zheng
谢昕辰