Convert the doc format to Markdown

[awxiaoxian2020]

closes #2691
closes #2564

it's in process.

[coveralls]

Coverage: 87.396% (+0.08%) from 87.313% when pulling b837a5d on awxiaoxian2020:markdown into 35262b0 on mybatis:master.

[harawata]

Hi @awxiaoxian2020 ,

Just to let you know that maven-site-plugin can handle multiple different formats (i.e. XDOC and Markdown) at the same time.
So, for example, if you are working on configuration first, it is OK to have a file structure as follows.

├── ja
│   ├── markdown
│   │   └── configuration.md
│   ├── resources
│   │   └── css
│   │       └── site.css
│   └── xdoc
│       ├── dynamic-sql.xml
│       ├── getting-started.xml
│       ├── index.xml
│       ├── java-api.xml
│       ├── logging.xml
│       ├── sqlmap-xml.xml
│       └── statement-builders.xml

If you want to convert all files in one PR, that is OK, but it'll take us longer to review and increase the chance of conflict with other contributors work.

[awxiaoxian2020]

@harawata It seems that we lost the skin...

[harawata]

@awxiaoxian2020 ,
I don't know much about site generation.
You should take a look at the doc files in the mybatis-spring project.
They were converted to markdown a while ago.
https://github.com/mybatis/spring/tree/master/src/site

[awxiaoxian2020]

@awxiaoxian2020 , I don't know much about site generation. You should take a look at the doc files in the mybatis-spring project. They were converted to markdown a while ago. https://github.com/mybatis/spring/tree/master/src/site

Thanks for your suggestions! I found I didn't download the mybatis-parent on my local machine when I build the site...the skin is defined in the parent site.xml.

[hazendaz]

@awxiaoxian2020 You may have to include that now with this effort. The other uses velocity and it inherits it from the parent automatically via maven.

[awxiaoxian2020]

close for clean commit. this PR is superseded by #2784.