How to correctly use nim doc when a project has unimported modules

[PMunch]

Well runnable examples should run during doc creation like they do now, 
otherwise they serve no purpose. The format would be almost exactly the same as 
the current jsondoc, but adding it bits and pieces here and there that the HTML 
generation would require. Have a look at the [Ratel 
documentation](https://ratel.peterme.net/documentation/board/i2c.html) for 
example, it was generated from the current jsondoc output, so most of the stuff 
is already there.