Docs: specify WebGLProgram#cameraPosition's space

docs/api/renderers/webgl/WebGLProgram.html

@@ -31,7 +31,7 @@
 		// = inverse transpose of modelViewMatrix
 		uniform mat3 normalMatrix;
 
-		// = camera.position
+		// = camera.position (in projection space)
 		uniform vec3 cameraPosition;
 		</code>
 		<code>