Fix readme.

git-svn-id: https://plugins.svn.wordpress.org/post-share-count/trunk@876260 b8457f37-d9ea-0310-8a92-e5e31aec5664
Fix plugin version.

git-svn-id: https://plugins.svn.wordpress.org/post-share-count/trunk@876263 b8457f37-d9ea-0310-8a92-e5e31aec5664