update doc

git-svn-id: http://plugins.svn.wordpress.org/wordpress-social-login@653117 b8457f37-d9ea-0310-8a92-e5e31aec5664
WSL 1.2.4

git-svn-id: http://plugins.svn.wordpress.org/wordpress-social-login@653132 b8457f37-d9ea-0310-8a92-e5e31aec5664
typo

git-svn-id: http://plugins.svn.wordpress.org/wordpress-social-login@653136 b8457f37-d9ea-0310-8a92-e5e31aec5664