Update compile script
Update compile script

Only download google closure compiler if it doesn't exist in the build
directory.

DDMAL/Neon.js,avorio/Neon.js,avorio/Neon.js,DDMAL/Neon.js,avorio/Neon.js,DDMAL/Neon.js,DDMAL/Neon.js,avorio/Neon.js