Add obsidian links support in docservices

[kevingzhang]

We will use Obsidian as our main markdown writing tool. The obsidian has link features which are the most important features. The [[link]] in obsidian will not directly convert to HTML link. So we may need to do the link conversion on our own.

We support three kinds of link

• [[link_md_file]] direct link to another md file, also convert to HTML.
• [[link_md_file | show_in_name]]. The link shows the "show_in_name" instead of the md file name.
• [[link_md_file # tag]] Link to the md file and scroll to the tag
• Combination of both | and #

If a folder support Obsidian, there will be a folder called .obsidian. There will be a file .obsidian/config in JSON format. Open this json object, check the "newFileLocation":"current". If it is current (it should be ), then we know that all [[link_file_location]] should be in the same folder as the parent file. If the "newFileLocation" is not "current", the link md files should be the same folder where .obsidian folder located.

Please replace all [[links]] to tag so that user can click the hyper link in browser when visiting our website

I saw your latest commit. based on the code, you have not solved the # tag yet. am I right?

[liyangwood]

Done with discussion. https://github.com/tearust/tea-docs/tree/main/test This is the sample folder structure. if test. please uncomment the https://github.com/tearust/tea-docs/blob/main/config.yaml#L80.