highway:steps should not be polygon

[rapkin]

In this issue aspectumapp/osm2geojson#7 we have problem with set of tags

"conveying": "forward",
"foot": "yes",
"highway": "steps",
"incline": "up",
"indoor": "yes",
"level": "-1",
"tunnel": "yes"

As you can see here https://wiki.openstreetmap.org/wiki/Tag:highway%3Dsteps highway: steps is not polygon.

Also your lib https://github.com/tyrasd/osmtogeojson detects this geometry as Polygon (method _isPolygonFeature), but because of line

...
ways[i].nodes[0].id === ways[i].nodes[ways[i].nodes.length-1].id // ... and forms a closed ring
...

this way produce LineString in result.

What do you think about this situation? Is it possible to add highway: steps to blacklist in this repository?