Improved baseurl parsing

The current implementation also replaces the URL's in the code snippets,
which may or may not be needed,

this could be an additional flag to avoid parsing / replacing inside code snippets or good to have would be to be able
to add files that can be ignored from going through the link replacement altogether.

Might need more through, but needs to be done

No file, test, or entry point is named. First inspect the baseurl and link-replacement implementation, then determine how code snippets and ignored files should be handled; done means the intended behavior and any flag or ignore mechanism are clearly defined and tested.

Written by the indexing model from the issue text.