* [WIP] Refine documentation

* get started done

* config refine

* train_test

* refine user guides

* add contribution

* add contribution

* refine visualization

* advanced tutorial

* advanced guides

* tricks

* refine zh doc

* refactor changelog

* [Doc] MMSeg 1.x Documentation

* revise index

* [Fix] Add avg_non_ignore in cross entropy loss

* [Fix] Add avg_non_ignore in cross entropy loss

* add docstring

* fix ut

* fix docstring and comments

* fix

* fix bce

* fix avg_factor in BCE and add more ut

* add avg_non_ignore

* add more ut

* fix part of ut

* fix part of ut

* test avg_non_ignore would not affect ce/bce when reduction none/sum

* test avg_non_ignore would not affect ce/bce when reduction none/sum/mean

* re-organize ut

* re-organize ut

* re-organize ut

* re-organize hardcode case

* fix parts of comments

* fix another parts of comments

* fix

* merge docs/ and docs_zh-CN/

* merge docs/ and docs_zh-CN/

* merge docs/ and docs_zh-CN/

* merge docs/ and docs_zh-CN/

* fix launch utility url

* fix launch utility url

* fix wrong pytorch doc url

* remove wrong links docs//

* multiple losses

* fix lint error

* fix typos

* fix typos

* Adding Attribute

* Fixing loss_ prefix

* Fixing loss_ prefix

* Fixing loss_ prefix

* Add Same

* loss_name must has 'loss_' prefix

* Fix unittest

* Fix unittest

* Fix unittest

* Update mmseg/models/decode_heads/decode_head.py

Co-authored-by: Junjun2016 <hejunjun@sjtu.edu.cn>

* Bump to v0.10

* change version

* refactor docs

* add docs

* add modelzoo

* refactor getting started

* [Improvement] Add markdown linter and fix linting errors

* fixed pip

* Generalized OHEM

* remove config

* update docstring

* fixed sort prob

* fixed valid_mask

* Fixed voc aug convert

* update getting_started.md

* add class balanced doc