Update README.rst

Author: pkkid

README.rst

@@ -10,7 +10,7 @@ Python-PlexAPI
 
 Overview
 --------
-Python bindings for the Plex API. Our goal is to match all capabilities of the official
+Unofficial Python bindings for the Plex API. Our goal is to match all capabilities of the official
 Plex Web Client. A few of the many features we currently support are:
 
 * Navigate local or remote shared libraries.