Added note on powers-of-two for tiling images

docs/api/textures/Texture.html

@@ -52,6 +52,10 @@
 		<div>
 		The default is THREE.ClampToEdgeWrapping, where the edge is clamped to the outer edge texels. The other two choices are THREE.RepeatWrapping and THREE.MirroredRepeatWrapping.
 		</div>
+		
+		<div>
+		NOTE: tiling of images in textures only functions if the edges of images are powers of two (2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, ...) in terms of pixels. Image sides need not be equal, but each must be a power of two. This is a limitation of WebGL, not Three.js.
+		</div>
 
 		<h3>[property:number magFilter]</h3>
 		<div>