Add some links to Facebook versions in the readme.

git-svn-id: https://plugins.svn.wordpress.org/wp-pat-twitter/trunk@923359 b8457f37-d9ea-0310-8a92-e5e31aec5664
Add initial version's `.pot` file to prep for language translations.

git-svn-id: https://plugins.svn.wordpress.org/wp-pat-twitter/trunk@923363 b8457f37-d9ea-0310-8a92-e5e31aec5664