Update ImageLoader.html

I couldn't find any reference to the FileLoader in the source code of the ImageLoader, I guess it has been removed.

docs/api/en/loaders/ImageLoader.html

@@ -12,7 +12,7 @@
 
 		<p class="desc">
 			A loader for loading an [page:Image].
-			This uses the [page:FileLoader] internally for loading files, and is used internally by the
+			This is used internally by the
 			[page:CubeTextureLoader], [page:ObjectLoader] and [page:TextureLoader].
 		</p>