Added code to exclude metabox JS files on non-DFADS post-new.php pages.

git-svn-id: https://plugins.svn.wordpress.org/ads-by-datafeedrcom/trunk@752603 b8457f37-d9ea-0310-8a92-e5e31aec5664
Updated readme.txt

git-svn-id: https://plugins.svn.wordpress.org/ads-by-datafeedrcom/trunk@752604 b8457f37-d9ea-0310-8a92-e5e31aec5664