Include deprecatation message for THREE.SplineCurve3

src/extras/curves/SplineCurve3.js

@@ -7,6 +7,7 @@ THREE.SplineCurve3 = THREE.Curve.create(
 
 	function ( points /* array of Vector3 */) {
 
+		THREE.warn( 'THREE.SplineCurve3 will be deprecated. Please use THREE.CatmullRomCurve3' );
 		this.points = ( points == undefined ) ? [] : points;
 
 	},