Update documents of MTLLoader

Author: wtlyu

docs/examples/loaders/MTLLoader.html

@@ -79,6 +79,7 @@ <h3>[method:null setMaterialOptions]( [page:Object options] )</h3>
 				<li>wrap: What type of wrapping to apply for textures. THREE.RepeatWrapping (default), THREE.ClampToEdgeWrapping, THREE.MirroredRepeatWrapping</li>
 				<li>normalizeRGB: RGBs need to be normalized to 0-1 from 0-255. Default: false, assumed to be already normalized</li>
 				<li>ignoreZeroRGBs: Ignore values of RGBs (Ka,Kd,Ks) that are all 0's. Default: false</li>
+				<li>equalizeTransparency: Use same defination of keyword Tr and d, or Tr = 1 - d. Open this option for obj exported from 3ds MAX, vcglib or meshlab. Default: false</li>
 			</ul>
 		</div>
 		<div>