Tested up to 4.0, now uses plugins_url() function

git-svn-id: https://plugins.svn.wordpress.org/wp-backgrounds-lite/trunk@986936 b8457f37-d9ea-0310-8a92-e5e31aec5664
Increased version number

git-svn-id: https://plugins.svn.wordpress.org/wp-backgrounds-lite/trunk@986938 b8457f37-d9ea-0310-8a92-e5e31aec5664