edit user manual

git-svn-id: https://plugins.svn.wordpress.org/form-maker/trunk@955971 b8457f37-d9ea-0310-8a92-e5e31aec5664
edit user manual

git-svn-id: https://plugins.svn.wordpress.org/form-maker/trunk@955973 b8457f37-d9ea-0310-8a92-e5e31aec5664