Minify scripts and styles

git-svn-id: https://plugins.svn.wordpress.org/visual-form-builder/trunk@892034 b8457f37-d9ea-0310-8a92-e5e31aec5664
Update readme with latest changes

git-svn-id: https://plugins.svn.wordpress.org/visual-form-builder/trunk@892035 b8457f37-d9ea-0310-8a92-e5e31aec5664