`remark-wiki-link` package refactoring

[olayway]

Acceptance

• [x] supports all of the formats below
  • [x] [[Wiki Link]] # relative wiki link
  • [x] [[Wiki Link|Alias]] # wiki link with alias
  • [x] [[some/folder/Wiki Link]] # obsidian absolute paths
  • [x] [[Wiki Link]] # obsidian shortened paths
  • [x] ![[...]] # for images and other embeds 🚧 some small bug in the syntax extension, but I'm too tired to spot it 😅
• [x] has extensive tests for
  • [x] syntax extension
  • [x] html extension
  • ~[ ] fromMardown extension~ removed, not needed
  • ~[ ] toMarkdown extension~ removed, not needed
  • [x] remark-wiki-link plugin itself
• [x] replace mocha with jest as it's used in all other projects
• [x] refactor to TS

Tasks

• [x] understand how the plugin and all the micromark extensions work
• [ ] ...

[olayway]

@rufuspollock I've created a draft of the PR for this. It's almost done (I know!!!), just need to debug image embeds.

[rufuspollock]

@olayway great job - well done.