[MapRoulette] Korean junctions

[Max]

I have added another challenge that i started almost 2 years ago, about 
Junctions in Korea.

http://maproulette.org/map/1460/

the Overpass query for it is simply

node["junction"="yes"](area:3600307756);
out body geom qt;

but this only covers a part of the problem.
actually it should be more complex, but I could not do it.
It should search for points without ways connected to it, that contain 
either of these characters: *ogeori, *오거리, *negeori, *네거리, *sageori, 
*사거리, *samgeori, *삼거리, *kyocharo, *교차로

Because many junctions in Korea don't even have the junction tag.


Also see
https://github.com/osmlab/maproulette/issues/345