Fixed overly-general admin CSS. Added better ways to access BFA variables for developers.

git-svn-id: https://plugins.svn.wordpress.org/better-font-awesome/trunk@899717 b8457f37-d9ea-0310-8a92-e5e31aec5664
Modified readme.

git-svn-id: https://plugins.svn.wordpress.org/better-font-awesome/trunk@899719 b8457f37-d9ea-0310-8a92-e5e31aec5664
Fixed readme typo.

git-svn-id: https://plugins.svn.wordpress.org/better-font-awesome/trunk@899720 b8457f37-d9ea-0310-8a92-e5e31aec5664