GLTFLoader: Update list of extensions in docs

docs/examples/en/loaders/GLTFLoader.html

@@ -30,10 +30,12 @@
 
 		<ul>
 			<li>KHR_draco_mesh_compression</li>
+			<li>KHR_materials_clearcoat</li>
 			<li>KHR_materials_pbrSpecularGlossiness</li>
 			<li>KHR_materials_unlit</li>
 			<li>KHR_mesh_quantization</li>
 			<li>KHR_lights_punctual<sup>1</sup></li>
+			<li>KHR_texture_basisu <i>(experimental)</i></li>
 			<li>KHR_texture_transform<sup>2</sup></li>
 			<li>MSFT_texture_dds</li>
 		</ul>

docs/examples/zh/loaders/GLTFLoader.html

@@ -28,10 +28,12 @@
 
 		<ul>
 			<li>KHR_draco_mesh_compression</li>
+			<li>KHR_materials_clearcoat</li>
 			<li>KHR_materials_pbrSpecularGlossiness</li>
 			<li>KHR_materials_unlit</li>
 			<li>KHR_mesh_quantization</li>
 			<li>KHR_lights_punctual<sup>1</sup></li>
+			<li>KHR_texture_basisu <i>(experimental)</i></li>
 			<li>KHR_texture_transform<sup>2</sup></li>
 			<li>MSFT_texture_dds</li>
 		</ul>