Add docs contents at README.md to easily find documents.
Issue: #2664 

![image](https://github.com/open-mmlab/mmsegmentation/assets/50650583/0763e108-f095-44d1-8e2a-ba2e83f02625)

![image](https://github.com/open-mmlab/mmsegmentation/assets/50650583/088e0945-55b4-4d3f-97bb-02e39dfafb5e)

![image](https://github.com/open-mmlab/mmsegmentation/assets/50650583/109e0320-d6a9-405f-b169-87acb5a0f94d)

![image](https://github.com/open-mmlab/mmsegmentation/assets/50650583/d1d72bde-40c0-451a-be6e-010f1f2d193b)

Repair invalid link of potsdam and vaihingen in docs

- support dsdl seg dataset 
- add dsdl dataset citest
- validated accuracy on voc2012 and cityscapes

## Motivation

For support with reading multiple remote sensing image formats, please
refer to https://gdal.org/drivers/raster/index.html

.

Byte, UInt16, Int16, UInt32, Int32, Float32, Float64, CInt16, CInt32,
CFloat32 and CFloat64 are supported for reading and writing.

Support input of two images for change detection tasks, and support the
LEVIR-CD dataset.

## Modification

Add LoadSingleRSImageFromFile in 'mmseg/datasets/transforms/loading.py'.
Load a single remote sensing image for object segmentation tasks.

Add LoadMultipleRSImageFromFile in
'mmseg/datasets/transforms/loading.py'.
Load two remote sensing images for change detection tasks.

Add ConcatCDInput  in 'mmseg/datasets/transforms/transforms.py'.
Combine images that have been separately augmented for data enhancement.

Add BaseCDDataset in 'mmseg/datasets/basesegdataset.py'
Base class for datasets used in change detection tasks.

---------

Co-authored-by: xiexinch <xiexinch@outlook.com>

Motivation

Typo in docs/en/user_guides/visualization_feature_map.md.

Modification

reature -> feature

Checklist

- [x] Pre-commit or other linting tools are used to fix the potential
lint issues.
- [x] The modification is covered by complete unit tests. If not, please
add more unit test to ensure the correctness.
- [x] If the modification has potential influence on downstream
projects, this PR should be tested with downstream projects, like MMDet
or MMDet3D.
- [x] The documentation has been modified accordingly, like docstring or
example tutorials.

## Motivation

As title, lead users to follow our migration document.

## Checklist

- [x] https://github.com/open-mmlab/mmsegmentation/pull/2801

## Motivation

- Create the `main` branch

## Modification

Modify links from `dev-1.x` to `main`

[Doc] Fix invalid links and standardize Chinese and English punctuation marks at zh_CN faq.md  (#2790)

As title #2750

## Motivation

1. It is used to save the segmentation predictions as files and upload
these files to a test server

## Modification

1. Add output_file and format only in `IoUMetric`
 
## BC-breaking (Optional)

No

## Use cases (Optional)

If this PR introduces a new feature, it is better to list some use cases
here, and update the documentation.

## Checklist

1. Pre-commit or other linting tools are used to fix the potential lint
issues.
3. The modification is covered by complete unit tests. If not, please
add more unit test to ensure the correctness.
4. If the modification has potential influence on downstream projects,
this PR should be tested with downstream projects, like MMDet or
MMDet3D.
5. The documentation has been modified accordingly, like docstring or
example tutorials.

## [Datasets] Add Mapillary Vistas Datasets to MMSeg Core Package .
## Motivation
Add Mapillary Vistas Datasets to core package.
Old PR #2484 

## Modification
- Add Mapillary Vistas Datasets to core package.
- Delete `tools/datasets_convert/mapillary.py` , dataset does't need
converting.
- Add `schedule_240k.py`  config.
- Add configs files.  
  ```none
  deeplabv3plus_r101-d8_4xb2-240k_mapillay_v1-512x1024.py
  deeplabv3plus_r101-d8_4xb2-240k_mapillay_v2-512x1024.py
  maskformer_swin-s_4xb2-240k_mapillary_v1-512x1024.py
  maskformer_swin-s_4xb2-240k_mapillary_v2-512x1024.py
  maskformer_r101-d8_4xb2-240k_mapillary_v1-512x1024.py
  maskformer_r101-d8_4xb2-240k_mapillary_v2-512x1024.py
  pspnet_r101-d8_4xb2-240k_mapillay_v1-512x1024.py
  pspnet_r101-d8_4xb2-240k_mapillay_v2-512x1024.py
  ```
- Synchronized changes to `projects/mapillary_datasets`

---------

Co-authored-by: Miao Zheng <76149310+MeowZheng@users.noreply.github.com>
Co-authored-by: xiexinch <xiexinch@outlook.com>

as title

---------

Co-authored-by: MeowZheng <meowzheng@outlook.com>

as title

as title

---------

Signed-off-by: csatsurnh <cshan1995@126.com>

## Motivation

En doc for visualization_feature_map.md and index.rst

## Modification

Add new file and change index.rst

as title

---------

Co-authored-by: Miao Zheng <76149310+MeowZheng@users.noreply.github.com>

as title

as title

as title

## 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>

## Modification
Add Chinese dataflow markdown

---------

Signed-off-by: csatsurnh <cshan1995@126.com>
Co-authored-by: csatsurnh <cshan1995@126.com>
Co-authored-by: Miao Zheng <76149310+MeowZheng@users.noreply.github.com>

as title

## Motivation

As the mmdet and mmcls are not very stabel, and mim can install repo
from source code, we remove them from mminstall and they won't be
installed automatically when run `mim install mmsegmentation`

## Modification

1. remove mmdet and mcls from mminstall
2. add explanation in faq

---------

Co-authored-by: MengzhangLI <mcmong@pku.edu.cn>

## Motivation

The registry now supports auto-import modules from the given location.

register_all_modules before running is no longer needed. The modules
will be lazy-imported during building.

- [x] This PR can be merged after
https://github.com/open-mmlab/mmengine/pull/643. The MMEngine version
should be updated.

Ref: https://github.com/open-mmlab/mmdetection/pull/9143