All highlights changes:
  - `@text.*` -> `@markup.*` (`strong`, `italic`, `link`, `strikethrough`; with exceptions; see below)
  - `@text.title` -> `@markup.heading`
  - `@text.literal` -> `@markup.raw`
  - `@text.reference` -> `@markup.link`
  - `@text.uri` -> `@markup.link.url` (in markup links)
  - `@string.special` -> `@markup.link.label` (non-url links)
  - `@punctuation.special` -> `@markup.list` (markdown lists only; move subitems from `@text.todo`)

Related to #315

- `@method` -> `@function.method`
- `@method.call` -> `@function.method.call`
- `@preproc` -> `@keyword.directive`
- `@define` -> `@keyword.directive`(`.define`?)
- `@storageclass` -> `@keyword.storage`
- `@conditional` -> `@keyword.conditional`
- `@debug` -> `@keyword.debug`
- `@exception` -> `@keyword.exception`
- `@include` -> `@keyword.import`
- `@repeat` -> `@keyword.repeat`