Added icons to admin pages

git-svn-id: https://plugins.svn.wordpress.org/contact-form-7-to-database-extension/trunk@1047540 b8457f37-d9ea-0310-8a92-e5e31aec5664
Stable tag: 2.8.21

git-svn-id: https://plugins.svn.wordpress.org/contact-form-7-to-database-extension/trunk@1047551 b8457f37-d9ea-0310-8a92-e5e31aec5664