dm:translation tags in non-modifiable files..?

@tbazant has the issue that he needs dm:translation tags in the intro documents for SES.
As translation tags need to be filled with either "yes" or "no" depending on the context, having translation tags in a file that is not supposed to be modified downstream is a conceptual issue. I am not 100% sure that translation tags really need to be part of the intro though ... would it not be enough to have them in the MAIN? Translation tags are file-based, so yes, they need to be in each individual file.

Specifically for the intro though, translation tags can just always be set to "yes" currently, because the intro pretty much always needs to be translated (and if none of the documents from the repo are translated, nothing will evaluate those tags, so what they are set to does not matter in that case anyway).

Zooming out and looking at the general issue though, this would only be properly solvable if we could mark up sections that can be changed in some way.

...
<!-- dk-ignore-start -->
<dm:translation>yes</dm:translation>
<!-- dk-ignore-end -->
...

But of course since doc-kit is supposed to be document type-agnostic, you'd have to make sure that whatever comment markup is needed for the file type is supported somehow. I don't know where to start, except maybe by defining that *.xml means that <!--these--> are comments and *.js means that //these\n are comments and ... where to stop. Seems like an endless hole.