fix broken link

docs/api/lights/DirectionalLight.html

@@ -43,7 +43,7 @@
 			[example:canvas_morphtargets_horse morphtargets / horse ]<br />
 			[example:misc_controls_fly controls / fly ]<br />
 			[example:misc_lights_test lights / test ]<br />
-			[example:vr_cubes cubes ]<br />
+			[example:webvr_cubes cubes ]<br />
 			[example:webgl_effects_parallaxbarrier effects / parallaxbarrier ]<br />
 			[example:webgl_effects_stereo effects / stereo ]<br />
 			[example:webgl_geometry_extrude_splines geometry / extrude / splines ]<br />