Implement alternative hyperlink anchors

[MacLotsen]

For package regulatory a lawyer only appends list items or articles (more like sections, instead of documents).
Therefore, the current behavior is unwanted, because now after every change every document referring to another needs to be recompiled, since the anchors are only list item bound (no structure in the anchor).

Situation:

1. First article
   1. First section
      1. First part
2. Second article
   1. First section
      1. First part
   2. Second section
      1. First part
      2. Second part

Current behavior:
The articles (top-level) are OK.
The first section of the second article will have a Item.2 anchor.

Wanted behavior:
The first second of the second article should be Article.1.Item.1.

This way, changed documents would not per se cause a recompilation of all documents, when a section or part is appended.