Create PreloadCORS.html as a copy of PreloadQueue.html. Will modify it as a test of PreloadJS with CORS requests in the next commit.
Add .htaccess that adds CORS headers for static assets; change URLs in PreloadCORS.html to fully qualified absolute URLs to test CORS requests. This causes the error "Line: 184 Error: 'loaded' is null or not an object" on IE8.
Work around progress error on IE8 with CORS requests