admin level 3 + state/country = disputed_reference_line

[tgrigsby-sc]

Need to handle hong kong / cyprus and a few other disputed admin_level 3 boundaries. This turns any admin_level 3 place=state/country into a place=disputed_reference_line using a new filter in boundaries.yaml

[nvkelso]

Please add some tests to ensure the point-of-view tags also get evaluated – so these new lines can be turned off and on in the stylesheet per different kind:xx values since a lot of these are disputed boundaries, too.