Additional checks when a license doesn't exist

[AdmiringWorm]

Currently with the newly added requirement for missing licenses when including binary files, the validator does not check if instead of the license there is a pdf file (or something similar) which may grant the maintainer distribution rights of the included binary file instead.

Suggestions:

1. Add additional checks for certain pdf file (by a naming convention) and allow the validator to pass validation if those are included.
2. Change the requirement to a note if any PDF file (or perhaps a doc, docx, etc) is included which mentions to the moderator to verify the maintainer have been granted distribution rights.
3. Change the requirement to a note if no normal LICENSE have been included.

Personally, I think the second option would be the best in this case (if possible)