Expand manifest description

Author: cpeterso

src/manifest.json

@@ -3,7 +3,7 @@
   "name": "Open Page in Private Window",
   "version": "0.4.1",
 
-  "description": "Open Page in Private Window",
+  "description": "Open a copy of the current page in a new Private Window.",
   "homepage_url": "https://github.com/cpeterso/open-page-in-private-window/",
 
   "applications": {