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#### What type of PR is this?
/kind documentation
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添加其中一个类别：
Add one of the following kinds:
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#### What this PR does / why we need it:
在 Readme 中增加应用市场链接。
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```release-note
NONE
```
#### What type of PR is this?
/kind cleanup
/area core
#### What this PR does / why we need it:
Bump up Halo to `2.9.0-SNAPSHOT` for developing Halo 2.9.0.
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind improvement
#### What this PR does / why we need it:
添加[爱发电](https://afdian.net/a/halo-dev)的赞助入口，以及在 README 上添加 Sponsors 图像，此图像会在 https://github.com/halo-sigs/sponsor-images 仓库中自动更新。
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind cleanup
/area core
#### What this PR does / why we need it:
- Update README
- Bump version to 2.8.0-SNAPSHOT
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind cleanup
/area core
#### What this PR does / why we need it:
Bump Halo to 2.7.0-SNAPSHOT for next development iteration.
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind chore
/area core
#### What this PR does / why we need it:
Upgrade version to 2.6.0-SNAPSHOT for next development iteration.
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind cleanup
/area core
#### What this PR does / why we need it:
- Bump up version to 2.5.0-SNAPSHOT for next development
- Update README.md
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
修复 Docker 快速运行的 `halo.security.initializer.superadminusername` 参数。
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind cleanup
/area core
#### What this PR does / why we need it:
Bump Halo version to 2.3.0-SNAPSHOT and update README.md
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
- Use arguments instead of environments.
- Change Docker image halo:2.0 into halo:2.1
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
更新 Readme 中快速开始的命令，提供初始管理员账号和外部访问链接的环境变量设置。
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
鉴于目前已不在 Release 中提供 Jar 包下载，Releases 下载数量的展示已经没有太大意思，所以去掉了 README 中的 Releases 下载数量徽章。
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
为 Halo 2.0 正式版本更新 README。
#### Special notes for your reviewer:
/hold
等待创建 2.0 的 release。
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
为 Halo 2.0.0-rc.1 更新 README。
#### Special notes for your reviewer:
/cc @halo-dev/sig-halo
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
1. 更新 2.0.0 的版本号。
2. 更新文档的版本号描述。
3. 更新标语。
#### Special notes for your reviewer:
/cc @halo-dev/sig-halo
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
Bump image tag in docker command.
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
#### What this PR does / why we need it:
The README.md is out of date due to [2.0.0-alpha.2](https://github.com/halo-dev/halo/releases/tag/v2.0.0-alpha.2) released.
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
/milestone 2.0
#### What this PR does / why we need it:
更新 README，提供 Halo 2.0 的演示环境信息。
#### Special notes for your reviewer:
/cc @halo-dev/sig-halo
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
/milestone 2.0
#### What this PR does / why we need it:
因为目前暂时没有提供 JAR 包，所以移除 README 有关使用 JAR 包运行的文档。
#### Special notes for your reviewer:
/cc @halo-dev/sig-halo
#### Does this PR introduce a user-facing change?
```release-note
None
```
#### What type of PR is this?
/kind documentation
/milestone 2.0
#### What this PR does / why we need it:
更新 README。
See https://github.com/halo-dev/halo/issues/2410 for more
#### Special notes for your reviewer:
/hold
#### Does this PR introduce a user-facing change?
```release-note
None
```
BugKing
