Updated help section with new multiple feed instructions.

git-svn-id: https://plugins.svn.wordpress.org/jsl3-facebook-wall-feed/trunk@802843 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added german language files.

git-svn-id: https://plugins.svn.wordpress.org/jsl3-facebook-wall-feed/trunk@802846 b8457f37-d9ea-0310-8a92-e5e31aec5664