Ruled Surface: strips off an edge chain, exact where possible (#762) (#1151)

Ruled Surface: strips off an edge chain in normal, tangent, angle or direction mode, exact planes/cylinders/cones where possible, mitred or round corners, stitched into one surface body. SurfaceRuled is noted under format 21. Closes #762.

crates/doc/src/feature_refs.rs

@@ -177,6 +177,7 @@ macro_rules! feature_walk {
                 FeatureKind::SurfaceUntrim { face, .. } => f(B(& $($m)? face.body)),
                 FeatureKind::SheetConvert { body, .. }
                 | FeatureKind::SurfaceExtend { body, .. }
+                | FeatureKind::SurfaceRuled { body, .. }
                 | FeatureKind::Unstitch { body, .. }
                 | FeatureKind::ReverseNormal { body, .. }
                 | FeatureKind::MeshConvert { body, .. } => f(B(body)),