Update constants.js

Update revision.

src/constants.js

@@ -1,4 +1,4 @@
-export const REVISION = '163';
+export const REVISION = '164dev';
 
 export const MOUSE = { LEFT: 0, MIDDLE: 1, RIGHT: 2, ROTATE: 0, DOLLY: 1, PAN: 2 };
 export const TOUCH = { ROTATE: 0, PAN: 1, DOLLY_PAN: 2, DOLLY_ROTATE: 3 };