Helper object to visualize a [page:Plane].
		var plane = new THREE.Plane( new THREE.Vector3( 1, 1, 0.2 ), 3 );
		var helper = new THREE.PlaneHelper( plane, 1, 0xffff00 );
		scene.add( helper );
		
		
		[page:Plane plane] --  the plane to visualize.
		[page:Float size] -- (optional) side length of plane helper. Default is 1.
		[page:Color color] --  (optional) the color of the helper. Default is 0xffff00.
		Creates a new wireframe representation of the passed plane.
		
See the base [page:LineSegments] class for common properties.
The [page:Plane plane] being visualized.
The side lengths of plane helper.
See the base [page:LineSegments] class for common methods.
This overrides the method in the base [page:Object3D] class so that it also updates the helper object according to the [page:PlaneHelper.plane .plane] and [page:PlaneHelper.size .size] properties.
[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]