or lines against lines. The constraints get rather screwed up
afterwards, of course.
So make arcs with the endpoints coincident into circles, instead
of nothings; since the first split of a circle produces that.
And don't warn after deleting just point-coincident or horiz/vert
constraints as a dependency; that's just a nuisance, because it
happens too often.
[git-p4: depot-paths = "//depot/solvespace/": change = 1884]
Jonathan Westhues